"We may conduct a joint operation with the United States against the PKK in northern Iraq ... We expect to work jointly, just as we do in Afghanistan," Erdogan said on a flight to Britain Monday, the mass-selling Hurriyet newspaper reported.

Erdogan said he got a signal that Washington might become involved during a telephone conversation with US Secretary of State Condoleezza Rice on Sunday.

"She was worried. I saw she was in favour of a joint operation," Erdogan said. "She asked for a few days' time and said she would come back to us."

He said President Abdullah Gul was to speak with US President George W. Bush soon.

Erdogan added that the issue would be also high on the agenda of his meeting with Bush in Washington, scheduled for November 5.

Wary of fresh turmoil in conflict-torn Iraq, the United States has repeatedly said it is against unilateral Turkish military action against the separatist Kurdistan Workers' Party (PKK).

The Turkish parliament last week gave the government a year-long authorisation to order a cross-border strike against the PKK.

Faced with mounting PKK violence, Ankara says it is running out of options, with neither the United States nor Iraq doing enough to stamp out the rebel bases.

It has accused the Iraqi Kurds, who run an autonomous administration in northern Iraq, of tolerating and even supporting the PKK, listed as a terrorist group by much of the international community, including Washington.