A special meeting looking into ways of revitalizing a key post-Cold War arms treaty has ended in Vienna without agreement.

Russia called the extraordinary session of NATO countries and other signatories of the Treaty on Conventional Armed Forces in Europe, hoping to reexamine the accord.  But the four-day meeting concluded Friday after participants failed to find sufficient common ground for a joint statement.

The treaty, signed in 1990 and updated nine years later, limits the number of troops and weapons that NATO and the now-defunct Warsaw Pact can deploy across Europe.  Russia has complained that the pact limits movements of Russian troops on their own territory.

Russian President Vladimir Putin has threatened to stop complying with the treaty, unless all NATO members ratify it.  Alliance states have delayed, and have pressed Moscow to withdraw troops from Georgia and Moldova. 

Assistant U.S. Secretary of State Daniel Fried told reporters Tuesday that the United States is ready to address Russian concerns.  He called the treaty one of the most successful arms accords, and he warned Russia against undermining it.

Some information for this report was provided by AFP, AP and Reuters.