Ukraine and its European allies have welcomed a US pledge never to recognise Moscow's 2014 annexation of Crimea, while Russia mocked Washington for living in a "different reality".
The declaration from secretary of state Mike Pompeo was seemingly intended to ease concern over US president Donald Trump's views on Ukraine and what he discussed with Russian counterpart Vladimir Putin in Helsinki earlier this month.
"The United States calls on Russia to respect the principles to which it has long claimed to adhere and to end its occupation of Crimea," Mr Pompeo said. "Through its actions, Russia has acted in a manner unworthy of a great nation and has chosen to isolate itself from the international community."
Mr Pompeo compared the US stance on Crimea to the so-called Welles declaration of 1940, by which Washington refused to accept the Soviet Union's occupation that year of Estonia, Latvia and Lithuania – a position that held until the Baltic states regained their independence in 1991.
“In concert with allies, partners, and the international community, the United States rejects Russia’s attempted annexation of Crimea and pledges to maintain this policy until Ukraine’s territorial integrity is restored,” Mr Pompeo said.
Room for manoeuvre
The declaration seems to leave Mr Trump little room for manoeuvre on Crimea, after he repeatedly refused to state clearly his position on Ukraine and reportedly told fellow leaders at last month's G7 summit that the Black Sea peninsula was part of Russia "because everyone there speaks Russian".
Ukrainian president Petro Poroshenko said on Thursday he was "sincerely grateful" to Mr Trump's administration for its "uncompromising position" and hoped the declaration would "finally deprive [the] Kremlin of its imperial illusions".
The European Union, Germany, Britain, Poland and other EU and Nato members also welcomed Mr Pompeo's statement.
It comes amid rising tension close to Crimea in the Sea of Azov – where Kiev says Russian border guards are harassing a growing number of ships en route to Ukrainian ports – and continued skirmishes and shelling in eastern Ukraine, where four years of fighting between Moscow's proxy militia and government forces have killed more than 10,300 people and displaced 1.6 million.
Russia laughed off the US declaration, however.
"We have heard nothing new," the Russian embassy in Washington wrote on Facebook. "We've just been convinced that our partners live in a different reality."
Russian foreign ministry spokeswoman Maria Zakharova also mocked Mr Pompeo's statement, and suggested that US policy could change at any time.
“But the joint action plan on the Iranian nuclear programme and the Paris agreement on the climate were also until recently official US policy,” she wrote. “That’s what [ex-US president Barack] Obama decided personally. Then Trump decided otherwise. We know the value of these ‘fateful declarations’.”
