MOSCOW (Reuters) - Russia said on Wednesday it may lift the veil of secrecy over its nuclear arsenal after a new strategic arms reduction treaty with the United States comes into force.

Russia's President Dmitry Medvedev (C) and Defence Minister Anatoly Serdyukov (L) visit a missile base in Teikovo in Ivanovo region, May 15, 2008. REUTERS/RIA Novosti/Kremlin/Vladimir Rodionov/Pool

In an attempt to bolster U.S. President Barack Obama’s non-proliferation efforts, the United States on May 3 dispensed with decades of Cold War secrecy and published the size of its U.S. nuclear weapons stockpile.

Russian Foreign Ministry spokesman Andrei Nesterenko praised the U.S. step and said Russia would consider doing the same after the ratification of the nuclear arms deal signed by Obama and Kremlin chief Dmitry Medvedev last month.

Russia and the United States hold more than 95 percent of the world’s nuclear weapons, enough to destroy the planet many times over, after first developing the weapons in top secret programs in the 1940s.

“After the Strategic Arms Reduction Treaty, which was signed by the Russian and U.S. presidents in Prague on April 8, comes into force, we will likewise be able to consider disclosing the total number of Russia’s deployed strategic delivery vehicles and the warheads they can carry,” he said.

If Russia follows suit, the world’s two biggest nuclear powers would come a step closer to much deeper cuts of thousands of non-deployed atomic weapons.

It could also raise the pressure on other nuclear powers -- such as China, Pakistan, India and Israel -- to disclose their nuclear capabilities, analysts said.

“This figure is one of the crown jewels of the Cold War when it comes to state secrets,” said Hans Kristensen, director of the Nuclear Information Project at the Federation of American Scientists in New York.

Nuclear weapons numbers were some of the most closely guarded secrets of the Cold War and spies on both sides expended vast amounts of energy trying to steal the figures or at least estimate the true strength of each others’ arsenal.

NUCLEAR POWERS

Obama has put nuclear disarmament and non-proliferation at the heart of his effort to “reset” ties with Russia, signing the landmark arms reduction deal last month with Medvedev and reviving a major civilian nuclear agreement.

Medvedev has praised Obama’s vision of a nuclear-free world as “beautiful and right,” though he has also said Russia will continue to develop new nuclear weapons and has called on other nuclear powers -- and those seeking to become nuclear powers -- to commit to cutting arsenals.

The Pentagon on May 3 said the United States had a total of 5,113 warheads in its nuclear stockpile at the end of September, down 84 percent from a peak of 31,225 in 1967.

The Bulletin of Atomic Scientists estimates Russia has a total inventory of about 12,000 nuclear warheads, including 4,600 deployed nuclear weapons and another 7,300 nuclear weapons in reserve or awaiting dismantlement.

Kristensen, who helped come up with the estimate for Russian weapons numbers, said that a Russian disclosure would put “serious pressure on the other smaller nuclear weapons states.”

“China has given some very vague references to their size but nothing with numbers yet. India and Pakistan have been absolutely quiet and so has Israel,” he said.