UNITED NATIONS, Feb 21 (Reuters) - Russia has urged U.N. states to vote against an "unbalanced and anti-Russian" move at the General Assembly by Ukraine and others to mark one year since Moscow invaded, as China said on Tuesday it could release a "position paper" on the war within days.

The 193-member U.N. General Assembly is due to vote later this week on a draft resolution stressing "the need to reach, as soon as possible, a comprehensive, just and lasting peace" in line with the founding United Nations Charter.

Ukraine and its supporters hope to deepen Russia's diplomatic isolation by seeking yes votes from nearly three-quarters of the General Assembly to match - if not better - the support received for several resolutions last year.

The draft text would again see the General Assembly demand Moscow withdraw its troops and call for a halt to hostilities. General Assembly resolutions are non-binding, but carry political weight.

"Even the eventual cessation of hostilities without a clear incentive for meaningful negotiations as well as rectifying the issues that lead to the crisis will not bring a long-lasting solution," Russia's U.N. Ambassador Vassily Nebenzia wrote in a letter to U.N. member states on Monday, seen by Reuters.

"There is no mentioning of 'dialogue' or 'negotiations'," he said of the draft. "If the text remains unbalanced and anti-Russian as it is now we ask Member States to vote against it."