U.S. officials are calling on Turkey and Iraq to exercise restraint, amid Turkish shelling of rebel bases inside Iraq. Turkish officials say the attacks are retaliation for a rebel ambush on Sunday that killed 12 Turkish soldiers. VOA's Cindy Saine reports from Washington, the U.S. is also calling on Iraq's Kurdish leaders to crack down on the rebels hiding in northern Iraq.

Turkish military and civilian leaders met Wednesday to discuss possible further action against rebels of the Kurdistan Workers' Party, or PKK.

In Washington, White House spokesman Dana Perino said the United States continues to urge the Iraqis and the Turks to exercise restraint, amid escalating tensions. She said both countries agree that the common problem and the common enemy is the PKK.

The PKK has been fighting for Kurdish autonomy in southeastern Turkey since 1984, and more than 30-thousand people have died in the conflict. Tensions have escalated in recent weeks following a series of attacks, and Turkey's parliament last week gave approval for military raids into northern Iraq to hunt for the rebels.

Turkish officials say the military has been firing at Kurdish rebel positions inside Iraq, but at a Pentagon briefing Wednesday, the Joint Chiefs of Staff Director for Operational Planning, Major General Richard Sherlock, said he was not aware of Turkish attacks across the Iraqi border.

"I don't know that there have been any Turkish airstrikes or cross-border operations into Iraq," said General Sherlock. "I know that there have been a small number, in the hundreds, of Turkish soldiers that have been stationed in Iraq for a number of years to observe and to gather information on the PKK."

Major General Sherlock stressed that the United States is working with both Turkey and Iraq to defuse tensions along the border.

"We are committed to security in that region," said Sherlock. "We believe this is an issue between Turkey and Iraq. We are working with both countries, as Turkey is a valued ally for a number of years, and Iraq is an ally in the war on terror. This is an issue right now that we are looking for diplomatic solutions and looking for a diplomatic answer."

Speaking to the House of Representatives Foreign Affairs Committee Wednesday, Secretary of State Condoleezza Rice said she had spoken with Turkish Prime Minister Recep Tayyip Erdogan and told him that a major incursion into Iraq would only cause more instability. But she also made clear that Iraqi Kurdish leaders have an obligation to act against the PKK.

"I spoke with Prime Minister Erdogan on Sunday, as well as with the Iraqi Kurds about this," said Condoleezza Rice. "I told Prime Minister Erdogan that the United States takes this extremely seriously. We said early on that Iraq should not be a place from which PKK terrorism can hurt Turkey."

A high-level delegation from Iraq is expected to visit Ankara for talks with Turkish officials on Thursday.