The leader of Turkey's ruling Justice and Development Party (AK Party), Recep Tayyip Erdogan, has taken over the prime minister's office, after he won a seat in parliament in Sunday's byelection.

Erdogan is under mounting pressure to introduce a motion sanctioning the deployment of U.S. forces in Turkey for a possible invasion of Iraq.

On Tuesday, Prime Minister Abdullah Gul resigned, making way for Erdogan. A new government will probably be formed by the end of the week.

Recep Erdogan

Erdogan's move into the prime minister's office will be a welcome boost to Washington's efforts to persuade Turkey to open its bases to U.S. military forces.

Earlier this month the Turkish parliament rejected a motion sanctioning deployment, after many deputies voted against their government.

According to a source close to the AK Party leadership, Erdogan is one of the strongest advocates of a U.S. deployment. Many in Ankara argue Turkey cannot afford to reject the billions of dollars of grants, loans and political guarantees offered by Washington to allow a deployment.

But Erdogan is also warning Washington that it has to be patient, indicating he wants to wait for the UN Security Council vote.

He's also concerned about the Kurds in northern Iraq. Turkey does not want them to form an independent state, which would encourage Turkey's Kurdish minority.

But for weeks an armada of U.S. warships has been waiting at Turkish Mediterranean ports. In an apparent attempt to calm rising U.S. frustrations some of the forces are now being allowed to deploy, albeit slowly.

It remains unclear whether this action is enough to allay U.S. impatience, although many in Ankara believe Washington has little choice but to wait.