US envoy Steve Witkoff said on Saturday he had held constructive talks with a Russian envoy in Florida as part of the US drive to end the conflict in Ukraine.

The meeting came just a day before Ukrainian and Russian negotiators were scheduled to meet in Abu Dhabi to discuss a US-backed plan to end nearly four years of fighting.

"Today in Florida, the Russian Special Envoy Kirill Dmitriev held productive and constructive meetings as part of the US mediation effort toward advancing a peaceful resolution of the Ukrainian conflict," Witkoff posted on X.

"We are encouraged by this meeting that Russia is working toward securing peace in Ukraine," he added.

US Treasury Secretary Scott Bessent, President Donald Trump's son-in-law Jared Kushner and White House Senior Advisor Josh Gruenbaum also attended the talks, he said.

The second round of talks in Abu Dhabi are set to start on Sunday, even if Ukrainian President Volodymyr Zelensky suggested earlier this week that it might be postponed because of the US-Iran crisis.

The Kremlin on Friday said President Vladimir Putin had agreed to a pause on striking Kyiv – ending Sunday – following a request by his US counterpart Donald Trump. (AFP)