(Recasts throughout; adds quotes from lawyer, paragraphs 7-8)
By David Brunnstrom
WASHINGTON, April 25 (Reuters) - The United States said on Friday it was examining lawsuits filed by the Marshall Islands against it and eight other nuclear-armed countries that accuse them of failing in their obligation to negotiate nuclear disarmament.
The Marshall Islands filed the lawsuits on Thursday in the United States and The Hague. The tiny republic in the Pacific Ocean was used for U.S. nuclear tests in the 1950s.
The U.S. State Department, however, defended the U.S. record on disarmament and said its stockpile of nuclear arms had been cut by 80 percent since the Treaty on the Non-Proliferation of Nuclear Weapons, commonly known as the NPT, took effect in 1970.
"The U.S. is dedicated to achieving the peace and security of a world without nuclear weapons, consistent with our obligations under the (NPT)," the State Department said in a statement.
"We have a proven track record of pursuing a consistent, step-by-step approach to nuclear disarmament - the most recent example being the New START Treaty," the State Department said, referring to a 2010 nuclear arms reduction pact with Russia.
The Nuclear Age Peace Foundation, a U.S.-based non-partisan advocacy group supporting the action by the Marshall Islands says the United States plans to spend an estimated $1 trillion on nuclear weapons in the next three decades and currently possesses nearly half of the world's 17,300 warheads.
"We are pleased that the U.S. is examining these suits, as they should," said Laurie Ashton, a lawyer for the Marshall Islands.
"The United States is spending hundreds of billions of dollars to modernize its nuclear weapons, which is the opposite of disarmament. Partial reductions to nuclear stockpiles don't matter if we're designing and building new weapons to take their place."
HIROSHIMA TIMES 1,000
The Marshall Islands, a group of 31 atolls, was occupied by Allied forces in 1944 and put under U.S. administration in 1947.
The Nuclear Age Peace Foundation said the United States conducted 67 nuclear weapons tests in the Marshall Islands from 1946 to 1958 and islanders were still plagued by the health and environmental effects.
The tests included the "Castle Bravo" detonation of a 15-megaton hydrogen bomb on Bikini Atoll in 1954, the largest the United States has ever conducted.
The detonation was estimated to be 1,000 times more powerful than the bomb that destroyed the Japanese city of Hiroshima in 1945, producing an intense fireball followed by a 20-mile-high (32 km) mushroom cloud and widespread radioactive fallout.
In the suits, the Marshall Islands accused all nine nuclear-armed states of "flagrant violation of international law" for failing to pursue the negotiations required by the 1968 Nuclear Non-Proliferation Treaty.
The lawsuits state that Article VI of the NPT requires states to negotiate "in good faith" on nuclear disarmament.
The Nuclear Age Peace Foundation said the five original nuclear armed states - the United States, Russia, Britain, France and China - were all parties to the NPT, while the others - Israel, India, Pakistan and North Korea - were bound by nuclear disarmament provisions "under customary international law."
The suit against the United States notes that it is not aimed at seeking compensation for the testing in the Marshall Islands, which became an independent republic in 1986.
But it says Washington should take "all steps necessary to comply with its obligations ... within one year of the date of this judgment, including by calling for and convening negotiations for nuclear disarmament in all its aspects."
Under bilateral agreements between the United States and the Marshall Islands, a Nuclear Claims Tribunal was established to assess and award damages to victims of the nuclear tests. But it has never had the cash to compensate fully for the damage done.
The Marshall Islands has a population of 68,000 people spread over 24 coral atolls. (Reporting by David Brunnstrom, editing by G Crosse)
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