The agreement was signed by US Secretary of State Condoleezza Rice and Poland's Radoslaw Sikorski at a ceremony also attended by Polish Prime Minister Donald Tusk and President Lech Kaczynski.

The site in Poland hosting 10 interceptor rockets and a giant radar in neighbouring Czech Republic will form the European part of a global system that Washington says it is assembling to shoot down ballistic missiles it fears could be launched by "rogue" states or militant groups such as al-Qaeda.

"This is an agreement that will establish a missile defence site here in Poland that will help us to deal with the new threats of the 21st century, of long range missiles ...

from countries like Iran or North Korea," Rice told reporters.

Russia sees the prospect of placing the shield in parts of central Europe that it used to control as a threat to its security.

It says Washington and Warsaw rushed into finalising the deal as a response to its military action in Georgia.

Some Russian politicians and generals have said Poland must be prepared for a preventive attack on the site in the future - a threat that Washington has dismissed as empty rhetoric.

Nato on Tuesday denounced threats against alliance member Poland as unacceptable.

Nato endorsed the missile defence plan for Europe at its summit in Bucharest in April even though some European allies are sceptical about its effectiveness and concerned it could lead to a new arms race.

The missile shield deal will now need to be approved by the Polish parliament, which is seen as formality because the government as well as the main opposition party support it.

Tusk's government bargained hard over the terms of the deal since coming to power last November, demanding greater military cooperation with the United States for agreeing to host the site.

The negotiations seemed stuck in July but a compromise was reached a month later.

Washington finally agreed to meet Poland's demand to equip its army with a battery of Patriot missiles as defence against a short-range attack Warsaw fears.

Nampa-Reuters

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