The US military warned Turkey Tuesday against destabilizing northern Iraq by carrying out a threatened cross-border raid on Kurdish rebels.

The US armed forces have a "great relationship with the military of Turkey," said Brigadier General Perry Wiggins, deputy director for operations of the Pentagon's Joint Staff.

But he cautioned: "As the secretary of defense (Robert Gates) has said, any disruption up in northern Iraq would not be helpful at this time."

Turkish Foreign Minister Abdullah Gul said Friday his country had drawn up plans for an eventual incursion into neighboring northern Iraq to pursue rebels of the Kurdistan Workers' Party (PKK) taking refuge there.

Gul warned that Turkey would activate its plans if the Iraqi authorities or the United States failed to curb the PKK, which is listed as a terror organization by both Ankara and Washington.

"Unfortunately, the level of cooperation by the United States is below our expectations," he said in remarks published by the Radikal daily.

Army chief Yasar Buyukanit has long been calling for a strike against PKK rebels based in Kurdish-run northern Iraq where, Turkey says, the PKK enjoys free movement and obtains arms and explosives for attacks on its soil.

But US officials, fearful of havoc in the only part of Iraq that has enjoyed relative calm, are anxious to forestall any Turkish intervention.

"We hope there is no unilateral military action taken on the other side of the Iraqi border," Gates said on June 3.

On June 18, Secretary of State Condoleezza Rice assured Ankara that the United States and Iraq were against any "terrorist" actions conducted from Iraqi territory against Turkey.