Russia-Ukraine updates: Putin suspends key US-Russia nuclear treaty

The U.S. believes the number of Russians killed or injured fighting in Ukraine is well above 100,000, according to people familiar with the matter.

One source said the U.S. believes more than 150,000 Russians have been killed or wounded, and another source said the total number was approaching 200,000.

The chairman of the Joint Chiefs of Staff, Gen. Mark Milley, said Friday that the Russian casualty number was "significantly well over 100,000." In November, Milley had said that "well over" 100,000 Russians had been killed or wounded.

That number includes Russians who have been killed in action, have died from wounds, or who were wounded and have been taken off the battlefield. The number of injured is believed to be higher than the number killed, one source said.

ABC News’ Luis Martinez, Ben Gittleson and Matt Gutman

CIA Director William J. Burns traveled to Kyiv and met with Ukrainian President Volodymyr Zelenskyy and Ukrainian intelligence officials last week, a U.S. official told ABC News.

The director "reinforced our continued support for Ukraine in its defense against Russian aggression," according to the official.

The Washington Post first reported the meeting earlier Thursday.

-ABC News' Cindy Smith

The Pentagon announced Thursday evening that it will provide Ukraine with $2.5 billion in additional aid for its efforts fighting Russian forces.

This is the 13th drawdown of equipment from the Department of Defense's inventories for Ukraine since August 2021, the agency said.

The package includes several weapons and equipment such as 59 Bradley infantry fighting vehicles and 90 Stryker armored personnel carriers, the DoD said.

-ABC News' Luis Martinez

The head of the United Nations nuclear watchdog group said Thursday that he is worried the world is becoming complacent about the "very precarious" situation posed by the Russian-controlled Zaporizhzhia nuclear plant in Ukraine.

Russian forces seized the plant, Europe's largest, in March 2022 and it has repeatedly come under fire in recent months, raising fears of a nuclear disaster. Rafael Grossi, director general of the U.N.'s International Atomic Energy Agency (IAEA), is working to set up a safe zone around the facility.

"I think the situation is very precarious," Grossi told reporters in the Ukrainian capital of Kyiv. "I worry that this is becoming routine, that people may believe that nothing has happened so far, so is the director general of the IAEA crying wolf?"

Grossi said two major explosions occurred near the plant on Thursday, adding to the alarming situation.

"We know every day that a nuclear accident or an accident having serious radiological consequences may take place," said Grossi before travelling to Moscow for talks with Russian officials.