The BBC is set to defy the prime minister by broadcasting footage of the bodies of two British servicemen killed in Iraq.

The corporation has said it will still air the programme despite an appeal from the prime minister and Tory leader Iain Duncan Smith.

The footage, first screened by Al Jazeera, is to be shown in the BBC2 Correspondent programme on Sunday.

A spokesman for the BBC insisted that it was "deeply sympathetic" to the families of Sergeant Simon Cullingworth and Sapper Luke Allsopp.

"We believe the subject covered is in the public interest," said a spokesman.

"From the beginning, the BBC kept the MoD informed of the content of the programme, and at the request of the MoD, they informed the families of the BBC's plans.

"Correspondent is an award-winning series, renowned for covering subjects sensitively and in great depth.

"It has covered the war in Iraq from various angles and this programme was one more piece in the jigsaw of this complicated subject."

But Number 10 has repeated its call for the BBC to shelve plans to broadcast the footage.

"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," said a spokesman.

"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."

Iain Duncan Smith also appealed for the programme's content to be reviewed.

"I call on the BBC to step back from this decision and to put the families, and those who have lost their lives in the service of their country, first," he told the Sun newspaper.

"They should not forget that these are real families, real lives and real tragedies."