The US military hopes to begin moving thousands of troops to Turkey as early as next week to take part in a possible invasion of Iraq under a tentative deal, US defence officials say.
The American officials stressed that a deal was not yet final, but Turkey's parliament was expected to approve it in a vote next week.
In return for allowing US troops to use bases in Turkey to launch an attack on Iraq, the United States is offering Ankara a multi-billion-dollar aid package aimed at cushioning its fragile economy against the shock of a possible war.
US officials say the aid package tentatively agreed by both sides would give Turkey $6 billion, of which $1 billion would secure an immediate $10 billion loan.
The roughly $5 billion in US cash assistance remaining would be split into economic grants and military aid. The United States has also offered Ankara up to $1 billion worth of oil from regional allies Saudi Arabia and Kuwait.
Earlier proposed US aid packages envisaged up to $20 billion in loan guarantees spread over three years, whereas the latest version allows Ankara to take the cash and loans up-front.
At the Bush administration's urging, US House of Representatives Speaker Dennis Hastert has privately assured Turkish officials that Congress would move swiftly to approve the aid once a final agreement is reached.
The United States plans to move up to 40,000 troops, most of them from the 4th Infantry Division, to Turkey. The division's heavy equipment, including tanks and other supplies already are on cargo ships headed for Turkey.
The troops would be flown there for quick arrival to join a force of nearly 200,000 US and British military personnel gathered in the Gulf region for a possible invasion of Iraq.