UNITED NATIONS, Feb 22 (Reuters) - Marking one year of war, Ukraine and Russia lobbied countries at the United Nations on Wednesday for backing ahead of a vote by the 193-member General Assembly that the United States declared will "go down in history."

"We will see where the nations of the world stand on the matter of peace in Ukraine," U.S. Ambassador to the United Nations Linda Thomas-Greenfield told the General Assembly.

The General Assembly appeared set to adopt a resolution on Thursday, put forward by Ukraine and supporters, stressing "the need to reach, as soon as possible, a comprehensive, just and lasting peace" in line with the founding U.N. Charter.

U.N. Secretary-General Antonio Guterres denounced Russia's invasion and said the Charter was "unambiguous," citing from it: "All members shall refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state."

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.

They argue the war is a simple case of one unprovoked country illegally invading another, while Russia portrays itself as battling a "proxy war" with West, which has been arming Ukraine and imposing sanctions on Moscow since the invasion.

"The West has ... brazenly ignored our concerns and continue bringing the military infrastructure of NATO closer and closer to our borders," Russia's U.N. Ambassador Vassily Nebenzia told the General Assembly.