Russia warns relations with US could be severed in 'note of protest'

Russia on Monday said it had summoned the U.S. ambassador to Moscow for a meeting to provide him a "note of protest" over President Biden's criticisms of Russia's war on Ukraine.

The tough statement from the Russian Ministry of Foreign Affairs warned that that relations between Moscow and the U.S. could be completely severed because of Biden's remarks and steps by the U.S. government to punish Russia over its invasion of neighboring Ukraine.

"It is emphasized that such statements by the American President, unworthy of a statesman of such a high rank, put Russian-American relations on the verge of breaking," the statement read, according to an English translation. "They warned that hostile actions taken against Russia would receive a decisive and firm rebuff."

Biden has in recent days called Russian President Vladimir Putin a "war criminal," a "thug" and a "murderous dictator" because of the atrocities committed by Russian forces during their nearly four-week military invasion of Ukraine.

The Russia statement said it had summoned U.S. Ambassador John Sullivan and handed him a "note of protest" over the "unacceptable statements."

State Department spokesperson Ned Price later confirmed to reporters that Sullivan met Russian officials and said the ambassador raised the cases of U.S. citizens detained in Russia.

"Ambassador Sullivan took advantage of this encounter to demand that the Russian government follow international law, and basic human decency for that matter, and allow consular access to all U.S. citizen detainees in Russia, including those in pretrial detention," Price said during a briefing, declining to characterize the message that the Kremlin sent to Sullivan.

The U.S. and its allies have imposed crippling sanctions on Russian banks and elites in response to the invasion, which has killed thousands and displaced millions in Ukraine.

Biden called Putin a war criminal last week in an off-the-cuff statement to a reporter after the White House had resisted doing so before a legal process could play out. Secretary of State Antony Blinken later said he personally agreed with the president's assessment.

Russia has launched strikes on civilian areas in Ukraine, including a theater and art school in Mariupol, and Putin as a result has been accused of committing war crimes. The Biden administration has made clear that any deliberate targeting of civilians would constitute a war crime.

The White House said last week that the U.S. has maintained a line of communication with Russia largely through Sullivan at the embassy in Moscow.

National security adviser Jake Sullivan also spoke with a senior Russian official last week to warn against the use of chemical or biological weapons in Ukraine, the most senior-level engagement between the two governments since the invasion began.

Updated at 2:42 p.m.