Although no details of how the two sides had overcome the final technical problems, and despite the final text awaiting approval by Presidents Bush and Yeltsin, the deal drew a warm bipartisan welcome in Washington.
Lee Hamilton, the influential Democrat who chairs the House Foreign Affairs Committee, called the deal to reduce US and former Soviet strategic weapons by two- thirds from their pre-1991 levels, 'a great gift to the nation and the world' and 'a good send-off' for Mr Bush three weeks before he leaves office.
The impetus for a speedy conclusion of the Start 2 treaty came from Mr Yeltsin who, during his visit to China earlier this month, surprised the Americans by saying Russia was ready to sign such an agreement.
After the 1990 conventional arms cuts in Europe, and the first Start treaty signed in Moscow in summer 1991, the Geneva pact is the third arms control agreement of the Bush administration - and in the nuclear field, by far the largest of its kind.
The eleventh-hour haggling this week does not affect the central plank of Start 2: the reduction of both nations' strategic warheads by 2003 to between 3,000 and 3,500 apiece, compared with a combined total of almost 15,000 allowed by Start 1 and the 20,000- plus in existence.
Specifically, the accord will eliminate multiple-warhead land- based missiles, considered the most destabilising category of weapons, in their entirety. The lingering disagreements, now apparently resolved, involved Russian demands to keep SS-18 silos for use by single warhead SS-25s, which are currently mobile, and to 'download' the six-warhead SS-19 to a single warhead missile.
The Americans have apparently given ground on both issues. In return however Washington wants to retain the right to equip its fleet of B-1 bombers with nuclear weapons, as existing B-52s are taken out of service.
If the deal is finalised, it will make Mr Yeltsin a hero again in the West, where politicians and businessmen have been starting to wonder if not about his commitment to reform then at least about his ability to achieve it. At home in Russia, it will cut a lot less ice. Hardliners opposed to dismantling the former Soviet Union's nuclear arsenal will be angry while the mass of the population will judge their leader not on his foreign policy achievements but on the concrete improvements to the economy he can bring in the near future.
The same goes for the standing of the Russian Foreign Minister, Andrei Kozyrev. A Start 2 treaty would reinforce his popularity abroad and remove any lingering doubts about him in diplomatic circles after the bizarre incident in Stockholm earlier this month when he made a mock Cold War speech, as he said, to show the West what life would be like if Russia reverted to Communism. But an arms deal would hardly help him at home where, along with the defence, security and interior ministers, he must face parliament soon to have his reappointment to the cabinet confirmed by Russia's deputies.
In concluding Start 2 with the Americans, Russia does not need to worry about the reaction of the three other former Soviet republics which inherited atomic weapons - Ukraine, Belarus and Kazakhstan - since they are supposed to hand over their missiles to Moscow and become non- nuclear states by 1998. But the Ukrainian parliament is dragging its feet over the ratification of the first Start treaty which did apply to the republic. Yesterday the head of the Kiev parliament's foreign affairs commission, Dmytro Pavlychko, said deputies could not address the issue until February or March because they had more urgent economic matters to debate and the more Washington pressured them for a vote, the more inclined they would be to take their time.
The Ukrainians insist they intend to ratify Start eventually but some Kiev politicians are speaking of the need for Western security guarantees to protect the republic from potential aggression by a nuclear Russia. Others are concerned that Russia will make a profit from dismantling the missiles of other republics. The US has promised Ukraine dollars 175m ( pounds 114m) in aid if it ratifies Start and assured the republic it will get a share of any money made from the sale of uranium from dismantled missiles.
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