Diplomatic sources in Moscow Monday said whatever remained of ties between Russia and the United States was on the verge of collapse after Washington’s Ambassador John Sullivan was handed “a demarche and a note of protest” in view of President Joseph Biden’s remarks calling Russian leader Vladimir Putin “a war criminal” amid the invasion of Ukraine. “On March 21, US Ambassador John Sullivan was summoned to the Russian Foreign Ministry where he was issued a demarche and handed a note of protest in connection with the recent unacceptable remarks by the head of the White House Joe Biden regarding the president of Russia,” the ministry said in a statement. Russian authorities insisted “such statements by the US president, which are unworthy of a statesman of such a high rank, bring Russian-US relations to the brink of breaking off.” “We have warned that hostile actions taken against Russia will receive a decisive and firm rebuff,” Moscow’s document went on. (https://en.mercopress.com/2022/03/22/diplomacy-between-us-russia-coming-to-an-end) Biden last week said Putin was a “war criminal” for launching an all-out invasion of Ukraine, which has caused numerous deaths and forced millions of people to flee their homes. The US Department of State later Monday that a meeting had taken place between Sullivan and the Russian government, during which Sullivan demanded that Moscow follow international law and called for consular access to US citizens detained in Russia.