NATO decided to keep its door open to Ukraine and Georgia, though it failed to launch the Membership Action Plan (MAP) for the two former Soviet republics.

Russia voiced its strong uneasiness and anger at this, as President Vladimir Putin challenged "the existence of the (military) bloc" on Friday.

He said his country did not believe that NATO's existence was not against Russia.

The circumstances have greatly changed since its creation, he noted, "Against whom does NATO exist?" he challenged.

On the Conventional Forces in Europe Treaty (CFE), NATO urged Russia to return to it, while Putin said his country was ready to do so if there was a compromise from Western nations.

"We are ready to return to the treaty but expect a mutual step," he told the NATO-Russia Council meeting on the last day of a three-day NATO summit.

Russia imposed a moratorium on the Conventional Forces in Europe Treaty (CFE) in December 2007 in protest against U.S. plans to deploy a missile defense system in Eastern Europe and NATO's ongoing expansion.

Moscow has insisted that NATO countries ratify the 1999 version of the treaty, which limits the stationing of troops and heavy weapons from the Atlantic coast to Russia's Ural mountains.