Talks between the top US and Polish diplomats here Monday are aimed at clearing up differences over a US plan to base an anti-missile shield in Poland, a senior US official said.
Polish Foreign Minister Radoslaw Sikorski will mainly "discuss missile defense" in Washington with US Secretary of State Condoleezza as well as with arms control expert John Rood, State Department spokesman Sean McCormack said.
"We continue to work on it (missile defense). It's a big issue for the Polish government. It's an important issue for us," McCormack told reporters without confirming the talks had started on schedule at 10:30 am (1430 GMT).
"We're devoting the time and the energy we think to try to work through any issues that may exist on either side," McCormack said.
In Warsaw, Polish foreign ministry spokesman Piotr Paszkowski told AFP the meeting had been called at Sikorski's request.
Sikorski was also due to meet with Republican presidential candidate John McCain and speak by telephone with Democratic White House hopeful Barack Obama, Paszkowski said.
Warsaw has refused to budge from its demands for extra security guarantees from Washington if it is to host US missile silos.
"We haven't rejected anything. The proof is that talks are continuing. We want to continue this to a happy conclusion. It's about reinforcing our security. We need to consider our interests," Sikorski was quoted as saying by Poland's PAP news agency.
The United States wants to base 10 interceptor missiles in Poland and a radar facility in the neighboring Czech Republic by 2011-13 to ward off potential attacks by so-called "rogue" states, notably Iran.
The shield would complete a broader US system already in place in the United States, Greenland and Britain.
A deal under which the Czech Republic would house the radar base was concluded in April.
Washington's talks with Warsaw have been grinding on since May 2007.
Warsaw has been lobbying Washington to provide a THAAD or Patriot-type air defense system in exchange for a Polish green light for hosting the silos.
On Friday, Polish Prime Minister Donald Tusk said Warsaw was sticking to its demands for a permanent arms presence guaranteeing Poland's security.
"We can agree anytime, tomorrow, in a week, in a month, as long as we have real guarantees for our security," he said.
Tusk's statement came after a telephone call Thursday with US Vice President Dick Cheney.
It also followed a series of conflicting statements from Warsaw and Washington regarding the status of talks.
While US officials had said "tentative agreement" had been reached, Poland's Defense Minister Bogdan Klich said no accord had been struck.
Russia is hostile to the idea of having the US missile shield on its doorstep -- and in its communist-era sphere of influence: both Poland and the Czech Republic were Soviet satellite states until 1989.
But the Kremlin has softened its line in recent months and appears to be focusing on getting security guarantees.
NATO, which both Poland and the Czech Republic joined in 1999, endorsed the US plan at a summit in April.
