NATO head Jens Stoltenberg said today he was "disappointed" by Russia's decision to quit the landmark Treaty on Conventional Forces in Europe as arms control efforts remained important to all sides.
"We are disappointed by the Russian decision to suspend participation in the joint consultative group of the CFE," Stoltenberg told a briefing at NATO's European military HQ in the Belgian city of Mons.
"We still support all efforts to have arms control and we believe the treaty is important... we believe to have consultations on arms control is important," Stoltenberg added.
President Vladimir Putin suspended Russia's participation in the CFE in 2007, charging that US deployments violated its terms. On Tuesday Moscow said it would no longer take part in the CFE's consultative committee's work in Vienna.
The CFE was finalised in 1990 at the end of the Cold War and set limits on the numbers of troops and military equipment that NATO and the then Russian-led Warsaw Pact could deploy in Europe.
Russia said today it was ready for talks on a new agreement but there were no immediate proposals on the table and NATO did not appear ready for talks.
The Ukraine crisis has plunged relations between Russia and the West to their lowest point since the end of the Cold War, with both sides trading barbs over who is to blame for the increase in tensions.