New pictures of captured Brits published

New pictures of some of the 15 captured British service personnel have been published by Iran.

The pictures show the sailors and Marines dressed in track suits and smiling.

They were released by an Iranian news agency after Prime Minister Tony Blair said that negotiations to free them were entering a "critical" phase.

Mr Blair said that the "door is open" to a diplomatic solution to the 12-day-old crisis, if the Iranians wanted one.

At the same time, he warned Tehran that Britain would take progressively tougher measures if there were no moves to free the detainees.

Mr Blair said: "This is a very critical time. The most important thing is that we get our people back safe and sound. That is what we are working for. The next few days are going to be vital in that."

He said that throughout the crisis, Britain had been pursuing a twin track approach with the Iranians.

"If they want to resolve this is a diplomatic way, the door is open," he said. "If that's not possible, then we have to take increasing tougher decisions."

His comments came after the head of Iran's Supreme National Security Council, Ali Larijani, said Iran was looking for a diplomatic resolution and did not want to put the detainees on trial.

Dr Larijani said that Iran favours a diplomatic solution to the problem and does not want to put the 15 captured British sailors on trial.

The Foreign and Commonwealth Office said it shared Tehran's "preference for early bilateral discussions".

But it added: "There remain some differences between us, but we can confirm we share his preference for early bilateral discussions to find a diplomatic solution to this problem."

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