Faye will not be freed

Iran may delay the release of Mrs Turney, 26, if Britain takes the issue to the UN Security Council or freezes relations, the country's top negotiator Ali Larijani said.

Speaking on Iranian state television, Mr Larijani said: "British leaders have miscalculated this issue."

If Britain follows through with its policies on the 15 British sailors and marines detained by Iran last week, Mr Larijani said "this case may face a legal path" - a reference to Iran prosecuting the sailors in court.

The news follows predictions the mother-of-one could soon be freed after Tehran yesterday suggested she could be released within a day or two.

Negotiations have been continuing today to gain access to the 15 captured service personnel who were paraded on Iranian television yesterday.

Downing Street officials insisted the Government simply wanted to secure the swift release of its personnel.

"We don't want a confrontation over this. We want this resolved as quickly as possible," a spokesman said.

"We are not seeking to put Iran in a corner. We are simply saying 'Please release the personnel who should not have been seized in the first place'."

Diplomats said they were alarmed by television footage of Mrs Turney - the only woman in the crew - apparently admitting the 15-strong boarding party had "trespassed" into Iranian territorial waters.

Iranian television also showed a letter to Mrs Turney's family in which she said she had written to the Iranian people apologising for what they had done.

However, the screening of the hostages was condemned as "completely unacceptable" by Foreign Secretary Margaret Beckett who said she was "very concerned" that she may have faced "pressure or coercion" at the hands of the Iranians.

Mrs Turney's family in Shrewsbury was awaiting further news today.

Her three-year-old daughter Molly is being cared for by her husband Adam in Plymouth. Mrs Turney and her husband were married at Oxon Church in Shrewsbury in 2002.

Today messages of support for Mrs Turney flooded in from across the country as diplomats continued to make efforts to free the captured service personnel.

Mick Keogh, Shropshire Army Cadet Force chief executive officer, said Mrs Turney had left the cadets based at Copthorne Barracks in about 1998 after she had reached the level of sergeant. He said: "Our heart went out to her and her family when we saw those pictures on the television.

"She will be locked up in a strange country and she will be on her own. That will be the hardest bit, but she is very strong-willed and I'm sure she will come through this."

A school friend of Mrs Turney's, Julie Pinches, of Castle Lane, Bayston Hill, who attended Meole Brace School with her, said that local people had been shocked to hear what had happened.