The Kremlin said on Tuesday that there is not yet a clear outline of a potential U.S.-Russia deal on Ukraine, but that the political will to move in the direction of an agreement is there.

In a call with reporters, Kremlin spokesman Dmitry Peskov said that contacts with the U.S. had been positive and useful, but that Moscow would not give a possible timeline for a peace settlement.

"There are no clear outlines of any agreement yet, but there is political will to move towards an agreement. And I repeat once again, we highly highly rate the constructive and meaningful contacts that we have had (with the U.S.)."

Ukraine and some of its European allies say Russia is not serious about wanting to end the conflict and have accused it of dragging out the talks with the U.S.

Russia says the issue is a complex one and that it is therefore not surprising that it will take time to find a long-lasting solution.

"Nevertheless, of course we would like to hope for the best, that the work will have positive results. We would not say exactly what the timeframe is here," said Peskov.