A second member of the British crew captured last week in the Gulf has been shown on Iranian television making an apology for illegally entering Iranian waters.
The British government has denounced the video as propaganda.
Crewman Nathan Thomas Summers - one the 15 British Naval personnel being held by Iran - apologized for the latest incident as well as one that occurred three years earlier.
"I would like to apologize for entering your waters without any permission. I know it happened back in 2004 and our government promised that it would not happen again. And again, I deeply apologize for entering your waters."
Summers was shown sitting with the female detainee and another serviceman.
The TV channel previously showed a similar taped confession from the woman. Britain maintains its naval personnel were in Iraqi waters when their vessel was seized by Iran.
Reacting to the video clip, British leader Tony Blair says parading and manipulating captured personnel disgusts people and, he says, it does not fool anyone.
"What the Iranians have to realize is that if they continue in this way they will face increasing isolation, the United Nations yesterday, the European Union today, we will be talking to other key allies over the weekend and we have just got to pursue this with the necessary firmness and determination but also patience because there is only one possible conclusion to this and that is that our personnel are released safe and sound."
The area near the mouth of the Shatt al-Arab waterway where the British patrol was picked up has for decades been claimed by both Iran and Iraq and its ownership has been hotly disputed.
Mr. Blair says that, based on satellite data from global positioning system technology, the naval and marine party was in Iraqi waters, not Iranian.
"The sooner the Iranian regime realize that they are not gaining anything from this, they cannot gain anything from this, it is perfectly obvious that these people were in Iraqi waters under a United Nations mandate, there is absolutely no question about the unlawful nature of their capture and therefore they have got to be released."
Meanwhile, for the first time in the week-long stand-off, the Iranian foreign ministry has sent a letter to the British embassy in Tehran.
British Foreign Secretary Margaret Beckett says London is carefully studying the wording of the document, and Britain will respond formally, but she says she is not very optimistic it represents a key potential breakthrough.
"There is nothing in the letter that suggests that the Iranians are looking for a way out of this difficult situation. We have been looking for a way out of it, for them for us and particularly for our service personnel from the beginning. I wish I saw any sign that this is what Iran is trying to do."
An Iranian news agency reports the message contains a call for Britain to avoid violating Iranian territorial waters in the future. While the dispute continues, the price of oil keeps climbing on the worldwide markets to above the 68-dollar mark.
