Russian President Vladimir Putin on Wednesday told the new U.S. Ambassador in Moscow, Lynne Tracy, that Washington was responsible for the "Ukrainian crisis" while accepting her credentials in a Kremlin ceremony.
Ties between Moscow and Washington have disintegrated since Putin sent troops to Ukraine last year.
Putin spoke a week after Moscow detained a U.S. reporter and charged him with espionage, sparking outrage.
"Relations between Russia and the United States, from which global security and stability directly depend, are going through a deep crisis," Putin told the new U.S. envoy as he swore in 17 ambassadors.
He said U.S. foreign policy "in the end led to the current Ukrainian crisis."
The longtime Russian leader has accused Washington of having orchestrated a revolution in Kyiv in 2014 after which he had no choice but to intervene.
Tracy is a Russian-speaking career diplomat who has worked in the former Soviet republics of Georgia, Kazakhstan, Kyrgyzstan and Turkmenistan.
She becomes ambassador during the worst crisis in years between the U.S. and Russia.
Last week, Russian authorities arrested U.S. journalist Evan Gershkovich on claims of "spying," accusations dismissed by Washington as "ridiculous."
Putin also told the new EU envoy to Moscow, Roland Galharague, that the bloc instigated "geopolitical confrontation" with Moscow.
Russia has been hit with a barrage of EU and U.S. sanctions since Putin launched his Ukraine offensive in February last year.