Poland rejected as insufficient on Friday a U.S. offer to boost its air defences in return for basing a "missile shield" on its territory but said it remained open to further talks with Washington.
The decision by Poland, a staunchly pro-American NATO ally, is a setback for the Bush administration's plans for global missile defence, which is intended to counter possible threats from what Washington calls "rogue states", particularly Iran.
"We have not reached a satisfactory result on the issue of increasing the level of Polish security," Prime Minister Donald Tusk told a news conference after studying the final U.S. proposal.
"The aim of the negotiations, in my view, is to enhance the security of our country. We still agree that it is fundamental for us to maintain our alignment with the United States, which has been, is and will continue to be our strategic ally."
In Washington, a White House spokesman said the United States would continue its talks with Poland.
"Discussions will continue," Gordon Johndroe told Reuters in an e-mail message.
The details of the U.S. offer have not been made public, though Tusk said it included a proposal to site Patriot ground-to-air missiles on Polish soil for one year.
In the months-long negotiations, Tusk's centre-right government had sought billions of dollars worth of U.S. investment to upgrade Polish air defences in return for hosting 10 missile interceptors.
"We are ready to accept proposals or corrections from the American side which would include our proposal to increase (our) security. We can do this in a day, a week, a month," Tusk said.
