Donald Trump has warned he will impose high tariffs and further sanctions on Russia if Vladimir Putin fails to end the war in Ukraine. Writing on his social media platform Truth Social, he said that by pushing to settle the war he was doing Russia and its president a "very big favour". Trump had previously said he would negotiate a settlement to Russia's full-scale invasion launched in February 2022, in a single day. Russia has not yet responded to the remarks, but senior officials have said in recent days that there is a small window of opportunity for Moscow to...