Putin has said repeatedly that he is prepared to negotiate an end to the war, which first began in 2014, but that Ukraine would have to accept the reality of Russian territorial gains, which are currently about 20% of its land. He also refuses to accept Ukraine joining Nato, the military alliance of Western countries.

Donald Trump pledged to end the conflict in Ukraine, but the war has proved harder to solve than he once thought. Now, he says he'll sanction Russia.