Turkey has warned the United States not to take the use of its border with Iraq for granted.
The Turkish President, Mr Ahmet Necdet Sezer, has been quoted as saying that a UN resolution authorising military action against Iraq is required before Turkey can consider opening its territory to US combat troops.
The reported comments come after Turkey warned the United States that an initial decision to back US military preparations against Iraq did not mean Ankara had taken an irreversible pro-US path.
Mr Recep Tayyip Erdogan, head of the ruling Justice and Development Party, today said "our American friends should not interpret this decision [to mean] that Turkey has embarked on an irreversible road" in support of the United States.
The warning came as talks between Turkey and the United States stalled on the amount of financial help Ankara is requesting from Washington to offset the economic impact of a war in neighbouring Iraq.
Earlier this month, the Turkish parliament voted to allow Washington to upgrade sea ports and air bases that could be used in an operation against Iraq.
Ankara has postponed a second vote on the deployment of US soldiers on Turkish soil, which was expected to take place today.
Mr Erdogan urged the United States to consider "with good will" Turkey's demands for financial assistance, adding that Ankara would not make unilateral "sacrifices" in support of a possible US operation against Iraq.
"The US is Turkey's strategic partner. But if we are to act together, if our support is meaningful and necessary to the US, then the US should take into account our sensitivities and consider with good will our demands," Mr Erdogan said.
"Otherwise, the partnership and the friendship will turn into constant sacrifices made by one of the sides and this is unacceptable," he added.