BAGHDAD -- In a statement that may gain traction in the U.S. presidential race, Iraq's national security adviser said Tuesday his country will not accept any deal for a prolonged U.S. presence in his country unless the agreement sets specific dates for the withdrawal of U.S.-led forces.

Interactive Iraq Map | Survey: Timetable Needed?

Mouwaffak al-Rubaie told reporters that the country "will not accept any memorandum of understanding that doesn't have specific dates to withdraw foreign forces."

Al-Rubaie said the timetable would be conditioned on the ability of Iraqi forces to provide security.

The comments by came a day after Iraq's prime minister, Nouri al-Malaki, said publicly that he expects the pending troop deal with the United States to have some type of timetable for withdrawal.

President George W. Bush, and the Republican who wants to succeed him, John McCain, have both been outspoken opponents of specific goals and timetables for the withdrawal of U.S. forces. Both have called such proposals recipes for defeat

Democrat Barack Obama, an early critic of the war, has supported legislation setting dates for withdrawal of U.S. troops, saying that such deadlines would force the Iraqi government to step up and take responsibility for political reconciliation.

Obama has planned an upcoming trip to Iraq that he said might refine, but not basically alter, his promise to quickly remove U.S. combat troops from the war.

The White House has been downplaying the statement.

In Japan, where Bush is attending the G-8 summit, White House spokesman Gordon Johndroe said al-Maliki has said previously that Iraq doesn't want a precipitous withdrawal "because of the security consequences."