US President Donald Trump is disappointed with both Russia and Ukraine in the negotiations to end the war. At the same time, the US believes it has "leverage" in the talks, according to White House spokeswoman Caroline Levitt during a briefing.

The Trump administration pushed to advance Ukraine peace talks that have stalled in recent weeks.

The US envoy held talks with the Russian president, meanwhile Moscow's ambassador to the UK told the BBC America is not Russia's ally.