BRITISH hostage Kenneth Bigley was made to plead for his life last night in the latest video from his abductors.

Reports said Mr Bigley was seen making a direct plea to Prime Minister Tony Blair to save his life in footage broadcast on an Islamic website.

The Foreign Office said it was aware of the reports and was investigating them, but had not seen the video.

The news is the latest twist in seven agonising days for the 62-year-old engineer's family, who are still waiting to hear his fate.

It came hours after Foreign Secretary Jack Straw warned there was little hope of securing the safe release of Mr Bigley.

In the latest video, the blindfolded man is seen wearing a pink shirt against a black and white backdrop covered in Arabic writing. In the grainy footage he says: "To Mr Blair, my name is Ken Bigley, from Liverpool.

"I think this is possibly my last chance. I don't want to die. I don't deserve and neither do the women deserve to be in prison.

"Please, please release the female prisoners that are held in Iraqi prisons. Please help them.

"I need you to help me, Mr Blair, because you are the only person now on God's earth that I can speak to.

"Please, please help me see my wife, who cannot go on without me."

Mr Straw said the Liverpudlian's family were now preparing themselves for the worst as he continued to face execution.

Militants holding Mr Bigley - who are believed to have beheaded both of his American colleagues in the past two days - have threatened to kill him as well unless Iraqi female prisoners held by the Americans were released.

Speaking from the United Nations General Assembly in New York, Mr Straw said: "We continue to do everything we can to secure Kenneth Bigley's safe release, but it would be idle to pretend that there's a great deal of hope."

Mr Straw said Britain could not get in to a situation "where we start bargaining with terrorists and kidnappers".

"If we were to, we would not make Iraq or anywhere else safer, we would make everywhere much less safe," he said.

The Tawhid and Jihad group boasted on Tuesday night of murdering a second American, Jack Hensley, after killing his fellow hostage, Eugene Armstrong, on Monday.

The executions have left Mr Bigley the remaining survivor of the three men, who were snatched from Baghdad last Thursday.

Video footage showing the death of Mr Armstrong was broadcast on a website and a body believed to be his was recovered.

A second body and severed head, feared to be Mr Hensley, were found in a black plastic bag in Baghdad's Amiriya neighbourhood earlier yesterday and handed to US forces.

Downing Street spokesman said of the latest video: "We are aware of the reports.

"The Foreign Office is looking into it and is keeping Mr Bigley's family fully informed.

"As the Foreign Secretary said earlier, we continue to do all we can to resolve the situation, but at the same time people understand how difficult the situation is."

Though painful, the video will give some hope to Mr Bigley's family after a day of setbacks.

It had been thought that one of the two high-profile women prisoners in US custody would be released.

But Qassim Dawoud, a security advisor to interim Iraqi Prime Minister Ayad Allawi, later said weapons scientist Dr Rihab Taha, nicknamed Dr Germ, would not be freed immediately.

Mr Straw, who spoke to US Secretary of State Colin Powell yesterday, said Britain had not been involved in discussions about the release of the female scientists and there had been no contact with the kidnappers.