Erdogan, who begins a two-day visit to Britain on Monday, said the separatist Kurdistan Workers' Party (PKK) was hiding behind the United States and Iraqi governments and using US weapons against Turkish forces.

"We have told (US President George W. Bush) about this issue but have not had a single positive result," he told The Times newspaper in an interview given before a PKK ambush near the Iraqi border left 12 soldiers dead Sunday.

The ambush raised concerns of an imminent Turkish military incursion into Iraq -- a move staunchly opposed by the United States.

"If a neighbouring country is providing a safe haven for terrorism... we have rights under international law and we will use those rights and we don't have to get permission from anybody," Erdogan said.

But military action could be avoided if the United States and Iraqis moved to expel the PKK, close down its camps and hand over its leaders, he added.

The prime minister, whose country is a key US ally and provides a vital supply route for its operations in Iraq and Afghanistan, said anti-US feeling was currently running high in Turkey.

He accused the US Congress of "firing a bullet" at US-Turkish relations because of its bill condemning as genocide the deaths of Armenians by Ottoman Turks during World War I.

"America might lost a very important friend," he said.

The US presence in Iraq had also fuelled resentment, he added, assessing that Washington had failed to meet its objectives since invading in March 2003.

"There's no success that I can see," he added. "There's only the deaths of tens of thousands of people. There's just an Iraq whose entire infrastructure and superstructure has collapsed."

Erdogan meets his British counterpart Gordon Brown Tuesday for talks touching on greater co-operation on security issues and Turkey's relations with the European Union, his office said October 18.