Iraq would like to see US forces withdraw as soon as feasible but setting a date for their departure would be a mistake, Iraqi Prime Minister Ibrahim al-Jaafari said.
"The presence of any foreign troops on our land means there is a weakness that we cannot by ourselves control the security situation," Mr al-Jaafari said in an interview with the Washington Post.
But a deadline would "play into the hands of the terrorists," he said on the eve of a meeting with US President George W. Bush at the White House today.
In the interview, Mr al-Jaafari called instead for accelerating the training of Iraqi troops, including a possible role for nations that are not a part of the US-led military coalition.
The newspaper said Mr al-Jaafari insisted that recent US-Iraqi offensives have improved security "dramatically", and that growing support from Iraqis had generated new public co-operation and information that has been helpful in combating insurgents.
He also insisted that Iraq would meet an August deadline for a new constitution -even though nothing has yet been written.
Some US legislators, including a few from the Republican Party, have called for a deadline to begin withdrawing American troops from Iraq.
But the White House and the Pentagon have rejected the idea, saying insurgents would simply wait for a withdrawal and then renew their fight.