Defence secretary Des Browne has said he was "sorry" for the fiasco over the sale of stories by the navy personnel held by the Iranians, as he announced two inquiries into what happened.
Appearing before the Commons for the first time since they were seized, Browne defended the conduct of sailors and marines during their time in captivity while making clear that he had no intention of resigning.
One inquiry, headed by a former Royal Marines general, would look at the events which led to their seizure in the northern waters of the Gulf last month, while the second would look at the media handling of the situation.
Despite a bitter attack by shadow defence secretary Liam Fox, who warned that his position was "becoming untenable", Browne was buoyed up a series of supportive comments by Labour backbenchers.
The defence secretary told the House that he had had made a "mistake" in not overruling a decision by the Navy to allow the 15 to sell their stories following their release by the Iranians.
Pressed by Fox on why he had not been prepared to say "sorry", Browne said: "It seems clear to me that I have expressed a degree of regret that can be equated with an apology. If you want me to say 'I am sorry', I am happy to say 'I am sorry.'"
Fox was scathing in his denunciation of the failure of anyone in Government to accept responsibility for the "national humiliation" which, he said, that Britain had suffered at the hands of "the pariah regime of Iran".
"In a more honourable time in politics, the resignation of a secretary of state who had overseen such a humiliating fiasco on his watch would have been an inevitability," he said.
"On the basis of his statement today, I believe his position is becoming untenable as he cannot command the necessary confidence in his political decision-making. That confidence is essential to the belief, the morale and strength of our Armed Forces. He and his colleagues must make their own judgments. Ultimately so must he."
Browne however rejected the idea that it had been a "national humiliation", insisting Iran had not been strengthened by what had happened, while making clear that he still enjoyed the support of the Service chiefs.