From The BBC News

US Secretary of State Condoleezza Rice travelled to Warsaw for the ceremony, after 18 months of negotiations.

The deal has angered Russia, which has warned the base could become a target for a nuclear strike.

Washington says the system will protect the US and much of Europe against missile attacks from “rogue elements” in the Middle East such as Iran.

The agreement, which has yet to be ratified by the Polish parliament, was signed by Ms Rice and Poland’s Foreign Minister Radek Sikorski.

‘Aimed at no-one’

Polish Prime Minister Donald Tusk said the negotiations had been “tough, but friendly”, adding that the deal would make both Poland and the US more secure.

Ms Rice said the signing of the document was an extraordinary occasion, adding that the agreement would help Nato, Poland and the US respond to “the threats of the 21st Century”.

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