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

Ukraine's foreign minister said in an interview with The Associated Press that he would like to have a peace summit in February, the one-year anniversary of the war, and would like it to be held at the U.N.

"The United Nations could be the best venue for holding this summit, because this is not about making a favor to a certain country," Dmytro Kuleba told the AP. "This is really about bringing everyone onboard and there is no better place than the United Nations to do that."

He continued, "Every war ends in a diplomatic way. Every war ends as a result of the actions taken at the battlefield and at the negotiating table. But the balance of what will be won on the battlefield and what will be won at the table, it remains to be seen."

Russia has so far rejected serious peace talks with Ukraine.

Meanwhile, Ukraine is calling for Russia to be expelled from the U.N. Security Council.

Ukrainian politician Iouri Loutsenko, the country's former prosecutor general, is leading the legal push to remove Russia as a permanent member of the U.N. Security Council: "It's about world peace. It's about world security, and it's about the rule of law in the world."

Loutsenko and his team argue that Russia's membership is illegitimate because the seat was initially granted to the Soviet Union in 1991, not the Russian Federation.

"In very simple terms, we have every legal argument to prove that Russia has never become a legitimate member of the U.N.," he told ABC News.

-ABC News' Britt Clennett

A Ukrainian drone attack on the Engels Air Force Base in southern Russia killed three, Russia’s Ministry of Defense said.

A spokesman for Ukrainian Air Force confirmed the attack, saying, “If the Russians thought the war would not touch them they were wrong.”

Russian air defence reportedly shot down a Ukrainian drone flying at low altitude, but falling debris caused the casualties in the overnight attack.

The Engels base lies just over 300 miles northeast of Ukraine's border with Russia. The facility has been repeatedly used by Russia to carry out missile strikes on targets in Ukraine.

Ukrainian forces had attacked another Russian air base on Dec. 5, killing three and damaging two strategic bombers.

-ABC News’ Britt Clennett

The Pentagon is weighing whether to carry out Patriot missile training for Ukrainian troops inside the United States, according to two U.S. officials.

If so, it would mark the first time Ukrainian forces trained inside the U.S. since the start of Russia's invasion.

The officials say the Army base at Fort Sill, Oklahoma, is being considered as the site for stateside training.

Last week, a senior defense official told reporters that several options were being considered for training that could last several months. However, no decision has been made and it is still possible that the training may take place in Germany, as previously reported.

Weapons systems training for Ukrainian troops has taken place only in Ukraine.

- ABC News' Luis Martinez

The United States is fighting a "proxy war" on "Ukrainian territory," Russia's ambassador to the U.S., Anatoly Antonov, claimed during an interview with Russian media Friday.

"Let me remind the viewers that a proxy war means an agent’s war, a war by proxy. Actually, this is what the Americans are doing on Ukrainian territory," Antonov said.

He continued, "Today, no one hides the true goals of the White House policy towards us. On all TV channels, political commentators talk about the need to intensify the U.S. proxy war against the Russian Federation."

Antonov stated that the risk of a clash "between the two great powers [Russia and the U.S.]" is "high."

- ABC News' Will Gretsky