A BBC Two film on Sunday will show images of the bodies of Staff Sergeant Simon Cullingworth, 36, and Sapper Luke Allsopp, 24, who were killed during an ambush near Basra.

The bodies were found in a shallow grave amid speculation that they had been summarily murdered. Close-up images were broadcast uncut by the Arabic news channel al-Jazeera, whose coverage of the war is the subject of the BBC documentary, Correspondent.

The Ministry of Defence asked broadcasters and newspapers not to use the images. The BBC has pixelated the faces of the men in the eight seconds of footage, a technique that masks the image.

However, Mr Blair backed a plea by relatives of the soldiers who said that broadcasting the footage would be “absolutely devastating for the families”.

A Downing Street spokesman said: “We have said to any television station showing pictures of soldiers injured or killed, the media should respect the feelings of families, especially at what must be a very difficult time for them.

“We fully endorse what the Ministry of Defence have said and support their decision to ask the BBC to reconsider and not broadcast this footage.”

The BBC said that it remained deeply sympathetic to all bereaved families and had informed the ministry that it was making the programme. But the corporation maintained that it was in the public interest for the documentary to include the scenes.

A spokesman said: “The programme deals with the differences in coverage of the war between the Arab world and the West, and the treatment of prisoners of war and casualties on both sides is central to the argument.

“Therefore, in the context of the programme, we believe that the short clip being shown, with footage of the soldiers heavily disguised, was in the public interest.”

Seargeant Cullingworth’s widow, Alison, 33, has written to Gavyn Davies, the BBC chairman, to try to dissuade the corporation from showing the pictures and has also written to Mr Blair asking him to ban the “cruel” footage.

The film, seen by The Times, depicts al-Jazeera’s search for explicit battlefield images which the company can claim as “exclusive”.

The BBC film includes al-Jazeera footage of dead Iraqis and American soldiers, as well as a sequence of US prisoners of war being questioned by Iraqi agents, which was condemned as a possible breach of the Geneva Convention.

In the film, Ibrahim Hilal, the news editor at the station based in Qatar, defends his decision to rush to air footage of the dead British soldiers, which had been passed on by Iraqi state television.

He says: “If I hide shots of American and British soldiers being killed, it is misleading for the audience. It is misleading for Arabs to imagine the only victims of this war are Iraqi children. We have to show the images and let the viewer judge if war is the most suitable way to solve problems or not.”

Mr Blair said initially, at a news conference with President Bush at Camp David, that the two men had been “executed”. Later, his spokesman acknowledged that there was not absolute proof that they had been.

• The BBC has apologised after receiving more than 200 complaints about a promotional trailer in which a family watches a woman fall to her death in medieval Britain. It was shown twice on BBC One on Tuesday night.

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