The Russian Ministry of Foreign Affairs said it summoned U.S. Ambassador John Sullivan on Monday in Moscow to formally protest President Joe Biden’s decision last week to label Russian President Vladimir Putin a “war criminal.”
Sullivan was told that Biden’s accusation had put “Russian-American relations on the verge of rupture,” according to a statement from the Foreign Ministry translated by NBC News.
Biden’s comment came hours Ukraine President Volodymyr Zelenskyy and other top officials met virtually with the International Criminal Court’s top prosecutor, who two weeks ago opened an investigation into possible war crimes by Russia.
A State Department spokesperson did not immediately respond to a request for comment from CNBC.
Sullivan is a Trump-era appointee whom the U.S. president asked to stay on at the start of Biden’s first term in 2021.
The diplomatic breakdown comes as Russia nears the one-month point in its unprovoked invasion of Ukraine, launched Feb 24.
An initial Russian infantry advance has largely stalled outside of country’s major cities amid fierce Ukrainian resistance. This has forced the Kremlin to shift tactics from a quick land war to a war of attrition marked by the shelling of residential areas in an effort to wear down and demoralize the nation.
White House press secretary Jen Psaki later said Biden was speaking from his heart about what he has seen on the news about the “barbaric actions by a brutal dictator.”
Psaki noted that there is a separate legal process to determine whether Putin has violated international law and committed war crimes. That process currently is underway at the State Department, she said.