TALLINN, Estonia (AP) — U.S. Secretary of State Hillary Rodham Clinton on Thursday ruled out an early withdrawal of U.S. nuclear forces from Europe, telling a NATO meeting that any reductions should be tied to a nuclear pullback by Russia, which has far more of the weapons in range of European targets.

No such negotiation with Russia is in the offing, and Moscow has shown little interest thus far in bargaining away its tactical nuclear arms.

Clinton also said the Obama administration wants NATO to accept missile defense as a core mission of the alliance, making it part of a broader effort to combat the dangers posed by nuclear, biological and chemical weapons and the missiles that delivery them. She said missile defense and nuclear weapons are complementary means of deterring an attack on the U.S. and its alliance partners.

A copy of her prepared remarks, delivered at a private dinner she attended with representatives of 27 other NATO member countries, was provided by her staff.

Shortly before she spoke, NATO Secretary General Anders Fogh Rasmussen told a news conference that in his view the U.S. nuclear weapons play a vital defensive role in Europe and should not be removed as long as other countries possess nuclear weapons.

"I do believe that the presence of the American nuclear weapons in Europe is an essential part of a credible deterrent," Fogh Rasmussen said.

Some European members of NATO, including Germany, have said the time has come for the U.S. to withdraw its remaining Cold War-era nuclear weapons from Europe. They cite President Barack Obama's pledge in Prague last year to seek a nuclear-free world. The Germans were joined by fellow NATO members Belgium, the Netherlands, Norway and Luxembourg late last year in requesting that the nuclear issue be put on the Tallinn agenda. It normally is dealt with by defense rather than foreign affairs officials.

But some newer NATO members who previously were part of the former Soviet Union or its Warsaw Pact military bloc are opposed to a U.S. nuclear withdrawal. They argue that the presence of the weapons is the surest guarantee of their territorial integrity.

In her dinner remarks, Clinton made clear that as NATO embarks on a discussion about the future of its nuclear weapons policy, it should be guided by an agreed set of principles — starting with a commitment that decisions will be made by the group, not unilaterally by Washington.

And she said that sticking with a nuclear NATO is consistent with Obama's Prague speech because the administration believes it should seek a balance between reducing the role of nuclear weapons in the world and meeting the future security needs of the alliance.

The Russian view is that its tactical nuclear weapons within range of European NATO countries are based on its own territory — unlike the American weapons. And so it wants the U.S. to take the first step by pulling its arms back to U.S. soil. This has not been a substantial irritant in U.S.-Russian relations, however, and those ties were given a boost earlier this month with the agreement on a new START treaty that reduces each side's allowable number of strategic nuclear weapons by roughly 30 percent.

Clinton did not say that U.S. nuclear arms should never be removed. But she made several points that appeared to exclude the possibility of bringing an early end to the presence of the weapons, which currently are stored on air bases in five European countries. In the event of war in Europe they would be assigned to combat aircraft flown by European crews — manifesting the basic tenet that allies must share the risks that come with a collective defense treaty hinged on a U.S. nuclear protection guarantee.

"As we consider NATO's approach to nuclear weapons," she said, "our deliberations should be guided by five principles." The first she mentioned was that as long as nuclear weapons exist, NATO will remain a nuclear alliance.

"Second, as a nuclear alliance, sharing nuclear risks and responsibilities widely is fundamental."

She added that it is the administration's "broad aim" to continue to reduce the role and number of nuclear weapons in its overall arsenal, which features about 5,000 strategic, or long-range, nuclear weapons — including about 3,000 that are in storage. And she called on the allies to broaden deterrence by pursuing territoral missile defense — in contrast to regional or global missile defense.

She laid out a formula for linking any future reductions in U.S. nuclear weapons in Europe to reciprocal actions by the Russians.

The Russians are believed to have about 2,000 tactical nuclear weapons although they have never confirmed the number.

Daryl Kimball, head of the Arms Control Association, a Washington-based advocate of nuclear disarmament, was critical of the tie to Russia.

"Linking removal of these militarily irrelevant weapons to Russian action on tactical nuclear reductions is naive and a recipe for inaction," he said in an e-mail exchange after Clinton delivered her remarks.

Fogh Rasmussen also credited President Barack Obama with putting "new wind in the sails" of the disarmament movement by calling for a nuclear-free world last April in Prague.

Clinton's dinner talk on nuclear policy formally launched a discussion that is due to climax in November when Obama and other NATO government leaders gather in Lisbon, Portugal, to endorse a rewriting of the alliance's basic defense doctrine.

At an earlier news conference with Estonian Foreign Minister Urmas Paet, Clinton said no one should doubt U.S. defense links to its allies.

"Let me be clear," she said. "Our commitment to Estonia and our other allies is a bedrock principle of the United States and we will never waver from it."

The nuclear element of the U.S. defense commitment to Europe takes several forms: the potential use of U.S.-based long-range nuclear missiles; the capability to quickly move U.S.-based short-range nuclear weapons to Europe in a time of crisis, and the storage of an estimated 200 nuclear bombs, designed to be dropped by short-range attack jets, in five European countries. Some Europeans have called for the forward-based bombs to be removed.

In its nuclear policy review this spring, the Obama administration said it hopes to engage Russia in a comprehensive negotiation covering all nuclear weapons on each side — not just those long-range weapons covered by the newly completed START treaty, but also those strategic weapons held in reserve by both countries as well as the "non-strategic," or shorter-range, weapons in Europe and Russia.

The U.S. government as a matter of policy will not confirm the location of U.S. nuclear weapons, but it is well known that the sites in Europe are in Belgium, the Netherlands, Germany, Italy and Turkey. The U.S. has had nuclear arms in Europe since the 1950s. It will not officially say how many remain, but private experts think it is about 200, down sharply from the 1980s.