This has been CNBC's live blog covering updates on the war in Ukraine. [Follow the latest updates here.]
The U.S. Defense Department is launching an interagency investigation into the source and the damage potential of a trove of classified documents that were leaked onto social media over the past few days. But the White House said the apparent leak will not impact U.S. security and intelligence assistance to Ukraine.
The documents contained sensitive information on not just Ukraine, but China, the Middle East and Africa, according to reports. They also revealed the rate of expenditure of Ukraine's S-300 air defense systems and a timeline suggesting when they would be depleted — and that they are running dangerously low.
Meanwhile, Finland's accession to the NATO military alliance is spurring Russia to bolster its air defenses along the countries' shared border, a Russian military commander said.
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U.S. intelligence leak could change our understanding of the war in Ukraine, says Harvard professor
Money Report
The U.S. military document leak is an opportunity to recalibrate our understanding of what is happening in Ukraine, said a political science professor at Harvard University.
Graham Allison, Harvard's Douglas Dillon professor of government, said the Ukrainian government has said its military is "killing ten times as many Russians as Russians are killing Ukrainians." But the intelligence leak suggests, instead, that there are four times as many Ukrainians killed, he told CNBC's "Squawk Box Asia."
"It's one of the rare occasions where you can study the differences between what is being said in public and ... what the realities are on the battlefield," he added.
A senior U.S. official previously told NBC News that the leaked documents are likely real, but some may have been altered before they were posted.
The classified documents that surfaced on social media last week include details on Ukraine's air defenses and plans for a spring offensive against Russian troops. Allison called this a "big loss" for Ukraine, as information about its air defenses "make it possible for Moscow to bring its aircraft and bombers back into the fight."
"The order of battle of your enemy ... [is] one of the most valuable things that an adversary can have," he said.
— Audrey Wan
U.S. designates WSJ reporter Evan Gershkovich wrongfully detained by Russia
The U.S. State Department officially declared that journalist Evan Gershkovich is being wrongfully detained in Russia, NBC News reported.
This designation means that the WSJ reporter's case will now be handled by the Office of the Special Presidential Envoy for Hostage Affairs and gives the government other resources to work on freeing him.
"Journalism is not a crime," State Department spokesperson Vedant Patel said in a statement. "We condemn the Kremlin's continued repression of independent voices in Russia, and its ongoing war against the truth."
Gershkovich was arrested on spying allegations in Russia.
— Riya Bhattacharjee
Belarusian opposition volunteers man a mortar position near Bakhmut
Belarusian volunteer soldiers from a regiment formed to defend Ukraine take up a front line position near Bakhmut in the Donetsk region of Ukraine.
Leaked Pentagon documents will not impact U.S. security assistance to Ukraine
The White House said the highly classified Pentagon documents that were leaked last week will not impact U.S. security and intelligence assistance to Ukraine.
The documents, which were circulated online, contained sensitive information on Ukraine's strategy on the battlefield, among other intelligence matters.
"We've been in touch with relative allies and partners," National Security Council spokesman John Kirby said when asked about the national security implications of the leaked reports.
Kirby added that the leaked intelligence, which has not been identified as authentic, would not impact U.S. assistance to Ukraine.
— Amanda Macias
Russian fighter jet nearly shot down a British spy plane over the Black Sea, report on leaked Pentagon documents reveals
A Russian fighter jet nearly shot down a Royal Air Force reconnaissance aircraft over the Black Sea last year, another stunning revelation from the leaked Pentagon documents, according to a Washington Post report.
On Sept. 29, a British RC-135 Rivet Joint surveillance aircraft was flying through international airspace close to Russian-occupied Crimea when it was buzzed by a squadron of Moscow's Su-27 fighter jets, the Post reported.
The Pentagon has not confirmed the validity of the leaked intelligence documents.
The incident, revealed in highly classified material that was leaked last week, could have drawn the NATO ally directly into the war in Ukraine. Under NATO's Article 5, if a member of the alliance is attacked, all members of the alliance will collectively respond.
— Amanda Macias
Three ships depart under Black Sea Grain Initiative as extension deadline looms
Three ships carrying 109,943 metric tons of corn and sunflower meal left Ukraine's ports of Yuzhny-Pivdennyi and Chornomorsk.
The vessels are destined for China, Portugal and Turkey.
The Black Sea Grain Initiative, a deal brokered in July between Ukraine, Russia, Turkey and the United Nations, eased Russia's naval blockade and reopened three key Ukrainian ports. The agreement was extended last month for 120 days and it is set to expire next month.
So far, more than 720 ships have sailed from Ukrainian ports since the deal launched.
— Amanda Macias
Ukraine, Russia send home around 200 troops in prisoner swap
More than 200 Russian and Ukrainian soldiers have returned home in a prisoner swap, the warring countries said Monday.
Russia's Defense Ministry said 106 Russian soldiers were released from Ukrainian custody as part of an agreement with Ukraine.
Andriy Yermak, Ukrainian President Volodymyr Zelenskyy's chief of staff, said that Russia freed 100 Ukrainian prisoners.
Neither announcement mentioned whether any intermediaries were involved in the agreement.
Some of the Ukrainian soldiers have severe injuries and illnesses, Yermak said in a statement published on Telegram.
He added that the latest of the sporadic prisoner swaps in the war that started in February 2022 was "not an easy one." He did not elaborate.
Ukraine's Coordination Headquarters for the Treatment of Prisoners of War alleged that almost half of the 80 men and 20 women soldiers who returned home "have serious injuries, illnesses or have been tortured." It presented no evidence for its claims.
According to Ukrainian news reports, one of the women prisoners is Valeriia Karpilenko, a border guard who had helped defend Mariupol's Azovstal steel plant. Last May, she married a Ukrainian soldier in the steel plant's basement while Russian forces surrounded the complex. Her husband was killed three days later.
The freed Russians were being flown on military transport planes to Moscow for medical treatment and rehabilitation, the Defense Ministry said.
— Associated Press
Leaked intel documents say Ukraine may soon run out of critical air defenses
More revelations are emerging from the leaked classified Pentagon documents that began surfacing on social media last week.
One document, dated Feb. 23 and marked "Secret," warned that Ukraine's S-300 air defense systems, which are from the Soviet era, would be depleted by May 2 at their current rate of expenditure, according to reporting by The New York Times. It isn't clear, however, whether that rate of expenditure has since slowed or sped up.
"Without a huge influx of munitions, Ukraine's entire air defense network, weakened by repeated barrages from Russian drones and missiles, could fracture, according to U.S. officials and newly leaked Pentagon documents, potentially allowing President Vladimir V. Putin of Russia to unleash his lethal fighter jets in ways that could change the course of the war," the Times wrote.
The intel leak may force Ukraine to change some of its military plans related to its anticipated spring offensive, according to a report. The legitimacy of the Pentagon documents is still being verified.
— Natasha Turak
Kremlin says no plan for cease-fire over Orthodox Easter
The Kremlin said there is no plan for a cease-fire in Ukraine over Orthodox Easter, which takes place on April 16 this year.
"So far, there haven't been any initiatives on this matter but our Holy Week has just begun. There have been no such initiatives so far," Kremlin spokesperson Dmitry Peskov said, according to Russian state media outlet Tass.
Earlier on Monday, U.S.-based think tank the Institute for the Study of War put out analysis suggesting that Russia might call for a cease-fire to delay Ukraine's anticipated counteroffensive, using respect for religion as a pretext.
Ukrainians and Russians observed Palm Sunday over the weekend, as Russian forces shelled numerous towns and cities around Ukraine. Local authorities say the shelling killed a number of civilians.
Russia denies that it targets civilians, despite more than a year of documented attacks on civilian residential areas and critical infrastructure such as power stations and hospitals.
— Natasha Turak
Eastern Ukrainian city of Avdiivka in 'total ruin,' less than 6% of prewar population left
The eastern Ukrainian city of Avdiivka has been reduced to "total ruin" by Russian shelling, Donetsk regional governor Pavlo Kyrylenko said.
"The Russians have turned Avdiivka into a total ruin," and those who still live there "risk their lives every day," Kyrylenko wrote on Telegram.
The city's prewar population of 32,000 has been reduced to a mere 1,800. The governor reported that a Russian airstrike hit and destroyed a multistory building on Monday.
"Fortunately, there were no casualties as all the residents of the building evacuated in time," he said.
— Natasha Turak
Zelenskyy is requesting a phone call with India's Narendra Modi, minister says
Ukrainian first deputy foreign minister Emine Dzhaparova arrived in India for a four-day visit to New Delhi, the first visit by a Ukrainian minister to India since Russia's full-scale invasion began in February 2022.
Ukraine would like to see India involved in helping find solutions to the conflict "to a great extent," Dzhaparova said. She also said that Ukraine's President Volodymyr Zelenskyy is requesting a phone call with Indian leader Narendra Modi, who has so far refrained from vocally condemning Russia for its invasion of its neighbor.
"We believe intensification of political dialogue on the highest level is first step towards this big goal. My president is requesting a phone conversation with the prime minister. We are looking forward to welcome him in Kyiv one day," Dzhaparova said in an interview with CNBC TV18.
— Natasha Turak
World Bank president condemns Russian detention of Wall Street Journal reporter
World Bank President David Malpass strongly criticized Russia's detention of American Wall Street Journal reporter Evan Gershkovich, who has been charged with espionage by the Russian government. Gershkovich, his family, The Wall Street Journal, and the Biden administration strongly reject the charges and have demanded his release.
"It's a brazen act by Russia. It violates press freedom, freedom of the press, which the World Bank Group has long recognized as vital. That includes the safety of journalists," Malpass told reporters.
"Press freedom increases transparency and accountability. It keeps a check on governance, it exposes corruption, transmits ideas, promotes innovation," he said, adding that he hoped Gershkovich is released and reunited with his family as soon as possible.
— Natasha Turak
South Korean lawmakers demand answers on leaked Pentagon documents claiming that CIA snooped on Seoul
The main opposition party in South Korea's government is demanding answers after documents purported to be classified Pentagon intelligence leaked onto social media, reportedly revealing — among many other things — that the CIA had been monitoring South Korean government conversations.
The discussions disclosed in the leaked documents reportedly exposed worries in Seoul that the weapons South Korea sells to the U.S. could end up in Ukraine.
South Korea has provided non-lethal aid to Ukraine and sells its advanced weaponry to NATO countries, but has a longstanding policy of not providing lethal weapons to war zones.
"If the report is true, it would be an action that can never be acceptable between allies of 70 years, and an infringement of sovereignty and diplomatic foul play that breaks bilateral trust head-on," Park Hong-keun, the leader of South Korea's Democratic party, told local media.
— Natasha Turak
Russian travelers say they fear one question: ‘Where are you from?’
For the past year, it's been harder and more expensive for Russians to travel abroad.
But some say that's only the beginning of their concerns.
With anti-Russian sentiment on the rise, several Russian citizens spoke to CNBC Travel about their worries, how they're treated when they travel, and what goes through their minds when people ask where they are from.
"You understand that you personally haven't done anything wrong, but you can't get rid of the idea that something's wrong with you personally," one Russian journalist who left her country because of the war told CNBC.
— Monica Pitrelli
Funeral for Russian military blogger Vladlen Tatarsky in Moscow
Hundreds of supporters turned out on April 8, 2023, for the funeral of a high-profile Russian military blogger killed in a bombing attack.
Vladlen Tatarsky, 40, was a vocal cheerleader of Russia's war in Ukraine. And while he was critical of Russia's defense establishment, he advocated for more aggression against Ukraine, for instance demanding the assassination of Ukrainian President Volodymyr Zelenskyy.
— Alexander Nemenov | AFP | Getty Images
Russian forces are 'expending significant resources for minimal gains' in Donetsk: UK MoD
The U.K. Ministry of Defence believes Russia has increased its assaults on the town of Marinka in Ukraine's eastern Donetsk Oblast, some 13 miles from Donetsk city.
The town has been fought over since 2014 and largely destroyed as a result, the ministry wrote in its daily intelligence update on Twitter. Still, Russian forces appear to be deploying substantial firepower over it.
Marinka "commands the approaches to Donetsk and the key H15 road," the ministry wrote. "Russia continues to give a high priority to resourcing operations in the broader Donetsk sector, including the Marinka and Avdiivka areas, expending significant resources for minimal gains."
— Natasha Turak
Zelenskyy condemns Russian shelling of civilian areas on Orthodox Palm Sunday
Ukrainian President Volodymyr Zelenskyy condemned Russia for its shelling of civilian areas on Sunday, which was Orthodox Palm Sunday, while mourning the deaths of those he said perished in these attacks.
"They hit a house, an apartment building," Zelenskyy said during his nightly address, referring to Russian forces. "Three people were inside. A man, a woman and a child — a girl, her name was Iryna, she would have turned 11 this year. She died. The man died too. My condolences ... The woman is in critical condition, in the hospital, she is being provided with medical care."
"This is how the terrorist state spends this Palm Sunday," he said. "This is how Russia puts itself in even greater isolation from the world, from humanity."
Ukraine is majority Orthodox Christian and celebrates Easter on April 16 this year.
— Natasha Turak
U.S. launches interagency effort to investigate intelligence leaks
The Pentagon has launched an interagency investigation into a slew of leaked classified intelligence documents on Ukraine and other countries, and is assessing the impact that these breaches could have on the national security of the U.S. and its allies.
"The Department of Defense continues to review and assess the validity of the photographed documents that are circulating on social media sites and that appear to contain sensitive and highly classified material," the Pentagon said in a statement. The Justice Department has also opened a criminal investigation.
The leaked documents cover a range of topics beyond just Ukraine, including China and the Middle East. For some, this suggests that the source of the leak may have been American.
"The focus now is on this being a U.S. leak, as many of the documents were only in U.S. hands," Michael Mulroy, a former Pentagon official, told Reuters.
— Natasha Turak
Russia plans to revamp air defenses, bolster protection along border with Finland
Russia will increase its air defenses along its north-west border with Finland in response to Helsinki's NATO accession, a Russian air force commander said in an interview.
Russian air defense forces have been challenged by Ukrainian strikes, and the country aims to revamp and reform them following the experience it's gained in the war so far, Lieutenant General Andrei Demin told Russian newspaper Red Star in an interview, according to Reuters.
Finland's new NATO membership means that the Western military alliance now occupies an additional 830 miles along Russia's border.
"In these conditions, the air defense forces are working out issues of protecting the state border in the north-west of the country in accordance with the increased threat level," Demin said, according to a Reuters translation.
— Natasha Turak
Read CNBC's previous live coverage here:
Secret Pentagon and NATO files leaked; Russia formally charges American reporter with espionage