The new treaty represents perhaps the most concrete foreign policy achievement for Mr. Obama since taking office 14 months ago and the most significant result of his effort to "reset" the troubled relationship with Russia

The United States and Russia have broken a logjam in arms control negotiations and expect to sign a treaty next month to slash their nuclear arsenals to the lowest levels in half a century, officials in both nations said on Wednesday.

After months of deadlock and delay, the two sides have agreed to lower the limit on deployed strategic warheads by more than one-quarter and launchers by half, the officials said. The treaty will impose a new inspection regime to replace one that lapsed in December, but will not restrict American plans for missile defence based in Europe.

Presidents Barack Obama and Dmitri Medvedev plan to talk on Friday to complete the agreement, but officials said they were optimistic that the deal was nearly done. The two sides have begun preparing for a signing ceremony in Prague on April 8, timing it to mark the anniversary of Mr. Obama's speech in the Czech capital outlining his vision for eventually ridding the world of nuclear weapons.

The new treaty represents perhaps the most concrete foreign policy achievement for Mr. Obama since taking office 14 months ago and the most significant result of his effort to “reset” the troubled relationship with Russia. The administration wants to use it to build momentum for an international nuclear summit meeting in Washington just days after the signing ceremony and a more ambitious round of arms cuts later in his term.

“This gives a boost” to the administration's efforts to build better ties to Russia, said Steven Pifer, a top State Department official under President George W. Bush who specialised in Russia and arms control issues. “There's still a ways to go and there are still difficult issues. But the last six months, it seems to be going pretty well and this adds to the positive in the relationship.”

More broadly, the White House hopes the treaty will build on the President's victory in the fight to overhaul healthcare, demonstrating progress on both the international and domestic fronts after months of frustration over unmet goals.

The new 10-year pact would replace the Strategic Arms Reduction Treaty of 1991, or START, which expired in December, and further extend cuts negotiated in 2002 by Mr. Bush in the Treaty of Moscow. Under the new pact, according to people briefed on it in Washington and Moscow, within seven years each side would have to cut its deployed strategic warheads to 1,550 from the 2,200 now allowed. Each side would cut the total number of launchers to 800 from 1,600 now permitted. The number of nuclear-armed missiles and heavy bombers would be capped at 700 each.

Neither the White House nor the Kremlin formally announced the agreement on Wednesday, pending the final telephone call between the Presidents. A Kremlin official, who spoke on condition of anonymity, said there was an agreement on the text of the pact, although not all the wording had been finalised. Robert Gibbs, the White House Press Secretary, said, “We're very close.”

Arms control proponents hailed the progress. Daryl G. Kimball, executive director of the Arms Control Association, called it “the first truly post-Cold War nuclear arms reduction treaty.” Richard Burt, a former chief START negotiator who now heads a disarmament advocacy group called Global Zero, said that the two Presidents “took a major step toward achieving their goal of global zero.”

The breakthrough ended nearly a year of tumultuous negotiations that dragged on far longer than anticipated. The two sides quarrelled over verifying compliance, sharing telemetry and limiting missile defence programmes. Mr. Obama restructured Mr. Bush's plans for an anti-missile shield in Europe, but Moscow objected to the new version as well and wanted restrictions. Mr. Obama refused. The two Presidents cut through disagreements during a telephone call on March 13.

The treaty will go for ratification to the legislatures in both countries, and the politics of Senate ratification could be tricky, coming at a polarised moment with a midterm election on the horizon. Republican Senators have already expressed concern that Mr. Obama might make unacceptable concessions. Ratification in the Senate requires 67 votes, meaning Mr. Obama would need support from Republicans.

Senators Mitch McConnell of Kentucky and Jon Kyl of Arizona, the Republican leaders, wrote Mr. Obama last week warning him that ratification “is highly unlikely” if the treaty contained any binding linkage between offensive weapons and missile defence, reminding him of his position “that missile defence is simply not on the table.”

Administration officials describing the draft treaty said its preamble recognised the relationship between offensive weapons and missile defence, but that the language was not binding. The treaty establishes a new regime of inspections, but the U.S. monitoring team that was based at the Votkinsk missile production factory until START expired would not be allowed to return on a permanent basis.

Russian analysts said Moscow was happy to have reduced what it saw as the overly intrusive inspection regime mandated by START but disappointed not to have secured restrictions on missile defence. The military was pressuring the Kremlin not to agree to arms reductions without limits on the American missile shield, even though both Mr. Bush and Mr. Obama have described it as aimed at Iran, not Russia. In the end, the Kremlin overruled the military because it wanted a foreign policy achievement. “The military does not have the influence that it did during Soviet times,” said Anton V. Khlopkov, director of the Centre for Energy and Security Studies in Moscow. “Back then, the military people, if they didn't run, they were among those who led the arms control negotiations from the Soviet side. Now, they have less of a role.”

Vladimir Z. Dvorkin, a retired Major-General and arms control adviser, said Moscow would retain the ability to scrap the new treaty if U.S. missile defences became a threat. “If, for example, the U.S. unilaterally deploys considerable amounts of missile defence, then Russia has the right to withdraw from the agreement because the spirit of the preamble has been violated,” he said.

Mr. Obama met at the White House on Wednesday with Senators John Kerry of Massachusetts and Richard G. Lugar of Indiana, the senior Democrat and Republican on the Senate Foreign Relations Committee, to brief them on the negotiations.

Mr. Kerry later said he would hold hearings between Easter and Memorial Day on the history of arms control and promised action by year's end. “I assured the President that we strongly support his efforts and that if the final negotiations and all that follows go smoothly, we will work to ensure that the Senate can act on the treaty this year,” Mr. Kerry said. — © 2010 New York Times News Service

(Clifford J. Levy contributed reporting from Moscow.)

Keywords: arms controlU.SRussia

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