There is nothing like an approaching deadline to get things moving, and this is what seems to be happening with the long drawn-out talks between Washington and Baghdad on the presence of US troops in Iraq. The UN mandate which legitimised the presence of foreign troops after the fact expires at the end of this year. Following a visit to Baghdad this week by the US Secretary of State, Condoleezza Rice, it appears that a bilateral agreement is nearing conclusion, which will set a timetable for a US withdrawal.

Preliminary details suggest that combat troops could be withdrawn from Iraqi cities by next June, and from the rest of the country by the end of 2011, if – and, of course, it is a big if – security conditions are judged satisfactory. It is noteworthy, though, that this judgement would be made not by the US alone, but by a joint US-Iraq commission. This is the latest evidence that the Iraqi government has been driving a hard bargain – which augurs well. It hints at a degree of authority, longer-term planning and negotiating strength in the government of Prime Minister al-Maliki that was conspicuous by its absence until recently. The fact that the agreement will set out a timetable – albeit one described by US officials as "aspirational" – is the most hopeful sign so far that an end to the Bush administration's Iraq adventure could be in sight. It also suggests a welcome recognition in Washington, as in Baghdad, that foreign troops anywhere have a habit of outstaying their welcome and then fuel the very insecurity they are supposed to remedy. The prospect of an agreement is also good news for Gordon Brown, confirming that the days of the British presence in Iraq are numbered, too.

There should, though, be room for caution. One reason why a provisional timetable has been disclosed now could have as much to do with US domestic politics as with the December deadline. Coming on the eve of the Democratic Party convention, it effectively undercuts Barack Obama's claim to be the candidate for an Iraq withdrawal and could thus assist the Republican nominee, John McCain. Let us hope that this is more than a political ploy in the great US presidential game.