MUNICH: Two year after Washington vowed to "reset" ties with Russia, US Secretary of State Hillary Clinton comes to Munich Saturday to launch a landmark nuclear pact between the former Cold War foes.

The new START nuclear arms reduction treaty will officially come into force when Clinton and Russian counterpart Sergei Lavrov exchange ratification documents at a security conference in the German city.

US Vice President Joe Biden used the same gathering of top defence officials in 2009 to state Washington's desire to press the "reset" button in relations with Russia which had cooled under the presidency of George W. Bush.

The US administration has touted the new Strategic Arms Reduction Treaty as a key element to improving ties with Moscow as well as a major step in US President Barack Obama's vision of a world free of atomic weapons.

The pact slashes existing warhead ceilings by 30 percent over the next 10 years and limits each side to 700 deployed long-range missiles and heavy bombers.

NATO chief Anders Fogh Rasmussen, who has made better ties with Russia a priority for the alliance, told the Munich Security Conference that the pact would "pave the way for a better security climate in the Euro-Atlantic Area."

"Far too often, the conference has been dominated by apparent divisions between NATO Allies and Russia," he said on Friday. "This year, I am delighted that it is no longer the case."

The original 1991 pact expired at the end of 2009 amid stark differences over how the two sides planned to proceed.

Many analysts see the new round of cuts as largely symbolic, however, because the chances of these heavy long-range weapons being used today are negligible.

But the pact provides an important starting point for far more pertinent discussions concerning smaller

Because potentially more dangerous nuclear weapons and other high-tech arms.

It will restore vital weapons verifications procedures and require the two sides to try and find a compromise over their diverging views on NATO's decision to erect a missile shield in Europe.

The US Senate and Russia's parliament adopted a series of non-binding amendments to the treaty that allowed each country to put their own spin on the first nuclear pact between the two former Cold War rivals in 20 years.

Most of the disagreements concern Washington's decision to push ahead with the European missile defence system, which it says is aimed at intercepting nuclear missiles fired from "rogue states" like Iran.

Russia, which fears that the missile shield may one day be turned into an offensive weapon, has agreed to explore the possibility of participating in the system but insists to be treated as an equal partner.