British officials said they expected all foreign troops to withdraw from Iraq within four years.
The statement came as British Prime Minister Tony Blair flew into Baghdad to show support to its new government today.
It was the firmest declaration yet from one of the two main allies in the 2003 invasion to topple Saddam Hussein on a date for pulling out troops from Iraq.
British PM Tony Blair meeting Iraqi Prime Minister Nuri al-Maliki today
Washington has said it is too soon to discuss such a timetable. Iraq's new prime minister, speaking at a joint press conference with Mr Blair, said he believed Iraqi forces could take over security in most of the country by the end of this year.
"There's an agreement and, according to this schedule for handing over security, Samawa and Amara provinces will be handed over to Iraqis in June and by the end of this year this operation will be completed except for Baghdad and maybe Anbar," Iraqi prime minister Nuri al-Maliki said.
Mr Blair, after meeting Mr Maliki in Baghdad's heavily fortified Green Zone, declined to be drawn on a timetable for withdrawal but stressed that foreign troops would pull out as fast as Iraqi forces were able to take over.
Mr Maliki's timetable, which would coincide with the expiry of a United Nations mandate for the US-led Coalition forces, is more ambitious than anything voiced publicly by US or British commanders, who stress that any withdrawal will depend on Iraqi forces being capable of ensuring security.
Samawa and Amara are southern, Shia provinces, largely peaceful and controlled by British troops. Their commanders have said they may withdraw from some provinces soon.
Anbar is the restive western desert stronghold of Sunni Arab insurgents.