The United States and Poland signed a deal Wednesday to place a US missile defense base just 115 miles from Russia's westernmost fringe - a move followed swiftly by a new broadside from Moscow against a system that it insists is aimed at Russia. US Secretary of State Condoleezza Rice and Polish Foreign Minister Radek Sikorski signed the formal agreement at the prime minister's chancellery in the presence of Poland's president and prime minister. Rice dismissed any suggestion that the 10 missile defense interceptors to be based in Poland - which Washington sought as a way to defend the US and Europe from a possible threat of long-distance missiles from Iran - constitute a threat to Russia. "Missile defense, of course, is aimed at no one," Rice said. "It is in our defense that we do this." Negotiators sealed the deal last week against a backdrop of Russian military action in Georgia, a former Soviet republic turned US ally, that has worried former Soviet satellites across eastern Europe. It prompted Russia's sharpest rhetoric yet over the missile defense system, which it has long fiercely opposed. Rice denounced a Russian general's threat to target NATO member Poland, possibly even with nuclear weapons, for accepting the facility. Such comments "border on the bizarre, frankly," Rice told reporters in Warsaw after signing the deal. "The Russians are losing their credibility," she said, adding that Moscow would pay a price for its actions in Georgia, but was not specific. "It's also the case that when you threaten Poland, you perhaps forget that it is not 1988," Rice said. "It's 2008 and the United States has a ... firm treaty guarantee to defend Poland's territory as if it was the territory of the United States. So it's probably not wise to throw these threats around." However, a few hours later, Russia's Foreign Ministry warned that Moscow's response to further development of the missile defense shield would go beyond diplomacy. It insisted that the plans are part of growing "US efforts to change the strategic balance of power in its favor." A ministry statement argued that the interceptor missiles to be based in Poland lack "any target other than Russian intercontinental ballistic missiles" and contended that the US system "will be broadened and modernized." "In this case Russia will be forced to react, and not only through diplomatic demarches," it said, without elaborating. The deal allows the US missile defense shield in Europe to take place following an earlier agreement to place its other element, a radar tracking system, in the neighboring Czech Republic - another formerly communist country now in NATO. Poles - whose country has been a staunch US ally in Iraq and Afghanistan - also saw in it a promise of safety for themselves in the face of a newly assertive Russia. "We have achieved our main goals, which means that our country and the United States will be more secure," Polish Prime Minister Donald Tusk told Rice after the signing. Along with the main deal, the two nations signed a so-called "declaration on strategic cooperation," which is to deepen their military and political partnership. It includes a mutual commitment to come to each other's assistance immediately if one is under attack - enhancing existing obligations both have as NATO members. The declaration also was accompanied by a promise from the US to help modernize Poland's armed forces and to place a battery of Patriot missiles there by 2012. Rice said the deal "will help both the alliance and Poland and the United States respond to the coming threats." Poland and the United States spent a year and a half in formal talks, which snagged in the final phase on Poland's demands for the Patriot missiles and other points. "After what happened in Georgia, I believe that this is good protection for us," said Kazimierz Dziuba, 49, a hospital worker in Warsaw. The Georgian conflict "made the Americans agree to this deal sooner because the Russians are getting too bossy," Dziuba said. Not all Poles are happy, however. Alina Kesek, an 82-year-old retired office clerk who lived through World War II, when Nazi Germany and the Soviet Union divided Poland between them, and then experienced four decades of Moscow-dominated communist rule, said the Patriot missiles were a "kind of provocation" toward Russia. "This means a threat from the Russian side," said Kesek. "I am not very pleased with this deal." Some residents in the northern Polish town of Redzikowo, where the missile defense facility will be located, fear it may expose them to retaliatory attacks or other dangers. Approval for the missile defense sites is still needed from the Czech and Polish parliaments. No date has been set for lawmakers in Warsaw to vote, but the deal enjoys the support of the largest opposition party as well as of the government.