President Barack Obama plans to remove all US combat troops from Iraq by August of next year, administration officials said Tuesday, ending the war that helped define his upstart presidential campaign - although a little more slowly than he promised. The withdrawal plan - an announcement could come as early as this week - could help Obama turn his attention to another campaign pledge: Deploying more troops to Afghanistan, a region he calls the central front in the war on terrorism. The timetable is a compromise. Removing so many people and tons of equipment presents logistical difficulties. Some commanders and advisers worry that security gains could backslide in Iraq if troops are brought out too soon, while others think the bulk of US combat work is long since done. "We are now carefully reviewing our policies in both wars, and I will soon announce a way forward in Iraq that leaves Iraq to its people and responsibly ends this war," Obama said in his address to Congress on Tuesday.