Russian President Vladimir Putin's "special military operation” into Ukraine began on Feb. 24, with troops crossing the border from Belarus and Russia. Moscow's forces have since been met with “stiff resistance” from Ukrainians, according to U.S. officials.
Russian forces retreated last week from the Kyiv suburbs, leaving behind a trail of destruction. After graphic images emerged of civilians lying dead in the streets of Bucha, U.S. and European officials accused Russian troops of committing war crimes.
A look at the two leaders at the center of the war in Ukraine and how they both rose to power, the difference in their leadership and what led to this moment in history.
Here's how the news is developing. All times Eastern.
Mar 13, 2022, 1:10 PM EDT
US and China to hold 1st in-person talks since Russia's invasion of Ukraine
White House national security advisor Jake Sullivan is scheduled to meet with Chinese foreign policy adviser Yang Jiechi in Rome on Monday, the first in-person, high-level talks between the two countries since Russia launched its invasion of Ukraine, an NSA spokesperson said on Sunday.
The Biden administration has been urging Beijing to use its influence with Moscow to condemn its war.
"The two sides will discuss ongoing efforts to manage the competition between our two countries and discuss the impact of Russia's war against Ukraine on regional and global security," NSA spokesperson Emily Horne said in a statement.
Luigi Mattiolo, diplomatic adviser to Italian Prime Minister Mario Draghi, and Sullivan are also scheduled to meet in Rome “to continue coordinating a strong, united international response to President Putin’s war of choice," Horne said.
-ABC News' Justin Gomez
Mar 13, 2022, 12:38 PM EDT
Zelenskyy claims nearly 13,000 Russian soldiers have been killed
Almost 13,000 Russian soldiers have been killed since the start of the invasion of Ukraine, President Volodymyr Zelenskyy said on Sunday.
In a short self-shot video address, Zelenskyy also said Russia had lost 1,000 military vehicles, 74 fighter jets and 86 helicopters. It was not immediately possible for ABC News to verify the figures.
A fire burns in an apartment building after it was hit by the shelling of a residential district in Mariupol, Ukraine, March 11, 2022.
Evgeniy Maloletka/AP
Zelenskyy added that a convoy of humanitarian aid was about 50 miles away from the besieged city of Mariupol in southeast Ukraine. He accused the Russians of blocking Orthodox priests who were accompanying the aid, which he said contains "100 tons of the most necessary things that Ukraine sent to its citizens."
"We have already evacuated almost 125,000 people to the safe territory through humanitarian corridors," said Zelenskyy of the situation in Mariupol.
The Mariupol City Council claimed Sunday that 2,187 civilians in the city have been killed since the invasion started on Feb. 24 and that Russia had dropped 100 bombs on Mariupol.
The latest information from the United Nations Human Rights Council shows that 579 civilians have been confirmed killed in Ukraine since the start of the invasion and another 1,002 have been injured.
-ABC News' Christine Theodorou
Mar 13, 2022, 12:04 PM EDT
Pope calls for an end to 'massacre' in Ukraine
Pope Francis issued a strong condemnation of Russia's invasion of Ukraine during his Sunday Mass, describing Russian strikes on children's hospitals and civilians as barbaric.
Pope Francis delivers his Sunday Angelus blessing from his studio overlooking St. Peter's Square in Vatican City, March 13, 2022.
Franco Origlia/Getty Images
"In the name of God, I ask, stop this massacre," the pope said, calling the Russian invasion an "unacceptable armed aggression."
Speaking at the Vatican, Pope Francis added, "God is the God only of peace, not of war, and those who support violence profane his name."
Mar 13, 2022, 4:18 PM EDT
American journalist killed in Ukraine
An American journalist has been killed in Ukraine, The New York Times confirmed Sunday.
Brent Renaud, a photographer and filmmaker, had worked as a contributor for the newspaper but was not on assignment for The Times when he was killed, according to a statement from the news outlet.
Brent Renaud attends the Peabody Awards in New York, May 31, 2015. Renaud, an American journalist, was killed in a suburb of Kyiv, Ukraine, on Sunday, March 13, 2022, while gathering material for a report about refugees.
Charles Sykes/Invision/AP, FILE
"We are saddened to hear of Brent Renaud's death. Brent was a talented filmmaker who had contributed to The New York Times over the years," the newspaper said in its statement posted on Twitter. "Though he had contributed to The Times in the past (most recently in 2015), he was not on assignment for any desk at The Times in Ukraine. Early reports that he worked for (The) Times circulated because he was wearing a Times press badge that had been issued for an assignment many years ago."
Kyiv's police chief later confirmed Renaud's death in a Facebook post.
A State Department spokesperson also confirmed Renaud's death.
"We offer our sincerest condolences to his family on their loss and offering all possible consular assistance," the State Department spokesperson said.
Time magazine editor in chief and CEO Edward Felsenthal said Renaud had been working in recent weeks on a Time Studios project focused on the global refugee crisis.
"We are devastated by the loss of Brent Renaud. As an award-winning filmmaker and journalist, Brent tackled the toughest stories around the world often alongside his brother Craig Renaud," Felsenthal said in a joint statement with Ian Orefice, president and COO of Time and Time Studios.
White House national security adviser Jake Sullivan told CBS News that he had just learned of Renaud's death Sunday morning and described it as "obviously shocking and horrifying."
"I will be consulting with my colleagues. We’ll be consulting with the Ukrainians to determine how this happened and then to measure and execute appropriate consequences as a result of it," Sullivan said. "I will just say that this is part and parcel of what has been a brazen aggression on the part of the Russians where they have targeted civilians, they have targeted hospitals, they have targeted places of worship and they have targeted journalists."
British Prime Minister Boris Johnson called Ukraine President Volodymyr Zelenskyy on Sunday and both leaders condemned the killing of Renaud, according to a read out of the call released by Johnson's office.