US President George W. Bush, facing Turkish threats of a military offensive in Iraq against Kurdish rebels, will assure Turkey's prime minister today he is committed to helping to combat the militants.
Turkish Prime Minister Tayyip Erdogan, who will meet with Bush at the White House, has made clear he wants concrete action to counter Kurdish rebels who have been launching attacks on Turkey from Iraqi soil.
If Mr Erdogan walks away from the meeting dissatisfied, there could be major repercussions for Bush's effort to stabilize Iraq where he has lately been touting progress.
Turkey, a NATO member with the alliance's second-biggest army, has sent up to 100,000 troops to the Iraqi border, backed by tanks, artillery and aircraft.
Ankara has said it may take cross-border action soon. Mr Erdogan is facing strong public pressure to go after the Kurdistan Workers Party (PKK) militants after a series of attacks on Turkish soldiers in recent weeks.
In one attack last month, PKK guerrillas killed at least 12 soldiers and captured eight. However, the rebels freed the eight soldiers yesterday, a development that could ease some pressure on the Turkish government to launch a major military operation.
Washington has urged Turkey to avoid sending thousands of troops across the border amid fears such an operation could destabilize one of the calmest parts of Iraq and cause a wider regional crisis.
Turkish officials have portrayed the meeting between Mr Bush and Mr Erdogan as a last chance effort to avert a military strike.
Outside the White House gates at least 100 protesters waved Kurdish flags and chanted "Long live Kurdistan!" and "Down, down Erdogan!"
Before leaving for Washington, Mr Erdogan told reporters he hoped for concrete steps from the United States to stop attacks that are "testing our nation's patience."
White House spokeswoman Dana Perino emphasized that Turkey was "a long-running ally" and that Washington shared its concerns about the PKK.
"We are concerned about the challenge posed by the PKK terrorists," she said. "They should be eradicated. We will work with Turkey and the Iraqis to make sure there is not a safe haven established for the PKK in that region."