Gordon Brown has privately backed American presidential candidate Barack Obama’s plan for all foreign troops to be pulled out of Iraq by summer 2010.

Downing Street sources say that the UK is ‘working to the same end’ as Mr Obama, who has said that he would remove all US troops from Iraq within 16 months if he won the presidential election in November.

The disclosure came as Mr Brown paid a surprise visit to Baghdad yesterday for talks with the Iraqi government.

Greetings: Gordon Brown meeting troops near Basra

His meeting with Iraqi premier Nouri al-Maliki, President Jamal Talabani and General David Petraeus, the head of the American military operation, came 24 hours before Mr Obama was also expected to arrive in Baghdad.

Mr Brown and Mr Obama are due to meet in Downing Street later this week.

But any suggestion of a tacit ‘deal’ between the two men is likely to be greeted with fury by Mr Obama’s presidential rival, John McCain, who has not pledged to withdraw American troops.

The complete withdrawal of UK troops on the same timetable would come as a relief to the British Armed Forces, who have complained about the pressure of maintaining 4,000 troops in Iraq and 8,000 in Afghanistan.

Gunning for you: Mr Brown strapped in and wearing a flak jacket on board an RAF Puma helicopter at Baghdad Airport

Britain has retained a larger troop presence in Iraq for longer than anticipated because of delays in training Iraqi forces to take their place.

However, the task has become easier in recent months because of a dramatic improvement in the political and economic situation in Basra, where the British troops are stationed.

Mr Brown yesterday set out four key objectives for the British operation in Iraq.

These were transferring responsibility for security to Iraqi people, the holding of democratic local elections, economic and social development and transferring the country’s airports from military to civilian use.

He said: ‘We are making very significant progress.

'There have been great steps made since my last visit in December.’

Publicly he refused to say when the last British soldier would leave Iraq.

‘I’m not setting an artificial timetable, but there has been significant progress,’ he said.