Over the weekend, Russian president Vladimir Putin signed a decree suspending the country's commitments under the 1990 Conventional Forces in Europe (CEF) treaty, citing "extraordinary circumstances ... which affect the security of the Russian Federation and require immediate measures" as the driving force for such move.

The 1990 pact - signed in the dying months of the Cold War - sets limits on the number of conventional weapons and military deployments across the continent and led to the removal of huge artillery stockpiles in the 1990s.

The treaty was updated in 1999 just before Vladimir Putin took over from Boris Yeltsin as the new Russian president. However, Washington and several European NATO countries have, up until now, failed to ratify the revised version of the treaty, asking Moscow first to withdraw its remaining forces from two breakaway regions in Georgia and Moldova.

Russia could no longer tolerate a situation in which it was complying with the treaty but its partners were not, the Kremlin spokesman was cited as saying by AP on Saturday. He also expressed hope that Russia's move would push Western nations to ratify the updated treaty.

The suspension from the pact – although not a full-scale withdrawal – means that Moscow will no longer exchange data on its arms deployments. It will take effect 150 days after all parties to the treaty have been notified.

The move, first threatened in April, is yet another setback in already tense relations between Russia and the West, first heightened following US plans to place parts of its anti-missile shield in Russia's backyard, Poland and the Czech Republic.

Mutual ties, however, have also been strained because of the ongoing dispute over Moscow's ban on Polish meat and the EU's hesitation to approve Moscow's application for the World Trade Organisation.

Several EU states have said they were alarmed by the Kremlin's latest move.

"We obviously regard Moscow's announcement with great concern", Germany's foreign minister Frank-Walter Steinmeier said, according to AP, adding that he hoped Russia will go no further than suspending the treaty.

The Czech foreign ministry said it hoped that "Russia will stop taking unilateral steps and will return to the negotiating table because negotiations, not threats, can produce positive results," the BBC reported.

However, former Soviet leader Mikhail Gorbachev – who signed the original treaty in 1990 – said "the decision of the head of state was an urgent call... to constructive dialogue and the implementation of the treaty".

He cited the American anti-missile shield and NATO members' failure to ratify an updated version of the treaty as justifications for the suspension, according to Interfax news agency.