Ukrainian forces and pro-Russian separatists have agreed to complete a withdrawal of heavy weaponry from their frontlines in eastern Ukraine, German Foreign Minister Frank-Walter Steinmeier said on Friday after a round of peace talks in Berlin.

More than 8,000 people have been killed in fighting between Kiev's forces and the separatists in Ukraine's eastern provinces of Donetsk and Luhansk since April 2014.

The violence has declined since the signing of a fresh ceasefire agreement in Minsk eight months ago, especially in recent weeks, though Western diplomats say the sides are far from implementing all 11 points of the peace plan.

"We've agreed ... to tackle the pullback of heavy weaponry now," Steinmeier said after talks with his Russian, French and Ukrainian counterparts. The separatists did not send a representative to the Berlin talks.

Steinmeier said it was encouraging that the ceasefire had now held without violations for 10 weeks, the longest period of calm since the signing of the peace deal.

The German minister, who with his French counterpart has been helping to mediate in the Ukraine conflict, said the two sides needed also to tackle the issue of who can run for office in planned local elections and who should monitor the voting.

In a statement from Paris, the French foreign ministry said there had been progress on several issues in the Berlin talks, including security in eastern Ukraine, political aspects of the Minsk accords and on the economic and humanitarian situation.

The European Union has imposed economic sanctions against Russia over its support for the separatists in eastern Ukraine as well as for its annexation of Ukraine's Crimea peninsula.