BRUSSELS, Nov 7 — Nato allies condemned a decision by Russia today to withdraw from the Treaty on Conventional Armed Forces in Europe, a key post-Cold War agreement, and said they would suspend its operation in response.

Russia formally withdrew from the security treaty, which limited key categories of conventional armed forces, blaming the United States for undermining post-Cold War security with the enlargement of the Nato military alliance.

"Allies condemn Russia’s decision to withdraw from the Treaty on Conventional Armed Forces in Europe (CFE), and its war of aggression against Ukraine which is contrary to the Treaty’s objectives,” Nato said in a statement.

The Russian move was its latest action that systematically undermined Euro-Atlantic security, it said.

"Therefore, as a consequence, Allied States Parties intend to suspend the operation of the CFE Treaty for as long as necessary, in accordance with their rights under international law. This is a decision fully supported by all Nato Allies.”

The United States said it would suspend treaty obligations effective Dec. 7.

Russia’s war against Ukraine and its withdrawal from the treaty "fundamentally altered” circumstances related to it and transformed participants’ obligations, White House national security adviser Jake Sullivan said.

Russia suspended participation in the treaty in 2007 and halted active participation in 2015.

Sullivan said that despite Moscow’s continued disregard for arms control, the United States and its allies will remain committed to effective conventional arms control. — Reuters