Five hours of talks between Russian President Vladimir Putin and US President Donald Trump's senior negotiator appear to have failed to produce a breakthrough on securing a Ukraine peace deal, BBC reported.

A Kremlin spokesman said the Moscow meeting was "constructive", but parts of the plan remained unacceptable to Russia.

Trump's special envoy Steve Witkoff and son-in-law Jared Kushner attended the talks after weeks of intensive diplomacy aimed at ending the war. The US team has not commented since leaving Moscow, according to BBC.