President Donald Trump said in an interview published Friday that “Crimea will stay with Russia,” the latest example of the U.S. leader pressuring Ukraine to make concessions to end the war while it remains under siege.

Soviet leader Nikita Khrushchev transferred Crimea from Russia to Ukraine in 1954, when both were part of the USSR, to commemorate the 300th anniversary of the unification of Moscow and Kyiv. In 1991, when the Soviet Union collapsed, the peninsula became part of newly independent Ukraine.

President Donald Trump hosted Norwegian Prime Minister Jonas Gahr Store and Finance Minister Jens Stoltenberg at the White House on Thursday. In remarks to reporters, Trump said he believes Russia is still interested in peace with Ukraine and later said he would hold off on considering additional sanctions until it’s clearer whether a ceasefire deal can be reached.