By Fredrik Dahl
VIENNA (Reuters) - China called on the United States and Russia on Monday to make further "drastic" cuts in their nuclear arsenals and said all states with atomic arms should undertake not to be the first to use them.
The development of missile defense systems which "disrupt" the global strategic balance should be abandoned, a senior Chinese diplomat also told a nuclear meeting in Vienna in a possible reference to U.S. plans that have angered Russia.
Under a treaty that entered into force in February 2011, Washington and Moscow are to limit the number of operationally deployed nuclear warheads to 1,550 - 30 percent lower than the ceiling a 2002 pact established.
But they still hold most of the world's nuclear arms - a fact underlined by the Chinese representative on the opening day of a two-week meeting in Vienna to discuss the nuclear Non-Proliferation Treaty (NPT), a 1970 pact.
China, Britain and France are the other three recognized nuclear weapons states in the world.
Ambassador Cheng Jingye, head of the Chinese delegation, said all nuclear weapons states should publicly undertake "not to seek permanent possession" of atomic bombs.
"As countries with (the) largest nuclear arsenals, U.S. and Russia should continue to make drastic reductions in their nuclear arsenals in a verifiable and irreversible manner," he said, according to a copy of his statement.
"Other nuclear weapon states, when conditions are ripe, should also join the multilateral negotiations on nuclear disarmament."
MISSILE SHIELD CONTROVERSY
The international community should develop, "at an appropriate time", a viable, long-term plan with phased actions, include a convention on the "complete prohibition of nuclear weapons," the Chinese diplomat added.
China closely guards information about its nuclear arsenal. However, the U.S. Department of Defense has said that China has approximately 130-195 deployed nuclear-capable ballistic missiles.
The head of the U.S. delegation, Ambassador Susan Burk, earlier told delegates that her country was making progress on disarmament and it would "detail those efforts this week."
Shortly after taking office in 2009, U.S. President Barack Obama set the goal of eventually ridding the world of nuclear weapons as a central theme of his presidency and pledged dramatic steps to lead the way.
Obama unveiled a revamped policy in 2010 renouncing development of new nuclear weapons and restricting use of those already in Washington's arsenal. He followed that up by signing the new START landmark arms reduction deal with Russia last year.
But momentum seems to have slowed on Obama's nuclear agenda and, with the November 6 presidential election looming, chances for major new advances look doubtful.
Burk said: "The United States has made clear on many occasions that it understands its special responsibility to take concrete steps towards a world without nuclear weapons by pursuing nuclear disarmament."
China's Cheng said nuclear weapon states should "earnestly reduce the risks" of atomic arms and negotiate a Treaty on Mutual No-First-Use of Nuclear Weapons.
The development of missile defense systems "which disrupt global strategic balance and stability should be abandoned," he added, without elaborating.
Washington says a planned European missile shield is meant to protect against a potential Iranian threat, but Russia says it risks tipping the balance of nuclear power between itself and the United States in Washington's favor.
(editing by Ron Askew)