Prime Minister Gordon Brown has urged the Iraqi captors of three British hostages to release them immediately.

It follows the handing over of the bodies of security officers Jason Creswell and Jason Swindlehurst, who were among five Britons captured by around 40 armed men at the Finance Ministry in Baghdad on May 29, 2007.

But the fate of the three others - IT consultant Peter Moore, from Lincoln, and two other guards named only as Alan, from Scotland, and Alec, from South Wales - is still unknown.

Mr Creswell and Mr Swindlehurst apparently died a year ago, an unnamed Iraqi politician, who is close to Iraqi Prime Minister Nuri al-Maliki, said.

The three remaining captives were reportedly to be released as part of an understanding that would allow the Shia militant group holding them to put down arms and join the political process.

The politician said: "There is no evidence that either confirms or denies the other hostages are still alive except for a piece of evidence in March regarding one of them."

The hostage-takers have released several videos of the men, including one in March that the politician was referring to.

Mr Brown said: "There can be no justification whatever for hostage taking and I call on those people who are holding the British and Iraqi hostages to return them as soon as possible - indeed immediately."

But Mr Moore's father Graeme said he was angry at the Government's handling of the case and described Foreign Secretary David Miliband as a "total waste of space".

He said: "We got the message yesterday morning that the bodies had been identified and Peter wasn't one of them, which gives me and Peter's friends hope. But unfortunately it isn't good for the other two families."

Mr Moore criticised the Foreign Office for not doing enough to help the men.

"They haven't done anything. They should have been straight in directing negotiations right from the beginning. Unfortunately the way Gordon Brown and David Miliband have handled this case is bad news for the other two families. Mr Miliband is a total waste of space.

"We will keep pushing on for Peter. We will do right until the end; until either Peter is released or we get the worst news."

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