For the past week he has been caught between the kidnappers’ leader, Abu Musab al-Zarqawi, one of the most ruthless terrorists to exploit the chaos created by the invasion of Iraq, and a family determined to do anything that might extricate a loved one from his terrible plight. As soon as it became clear that the Briton had been seized by Zarqawi’s Tawhid and Jihad group, there seemed to be little hope for him. But the way the crisis has unfolded has made Mr Blair look unimaginative as well as impotent.Last Saturday, understandably, the Prime Minister said little in response to the video showing the three Westerners were in Tawhid and Jihad’s hands. By Monday, however, the decapitation of the first American hostage, Eugene Armstrong, had been posted on the internet.

The killers were demanding the release of Muslim women held in Iraqi jails, but the authorities said there were just two: both scientists suspected of working on chemical and biological weapons.At this the Bigley family broke its silence. Craig Bigley, Kenneth’s 33-year-old son by his first marriage, said in an emotional appeal on television: “I ask Tony Blair personally to consider the amount of bloodshed already suffered. Please meet the demands and release my father – two women for two men. Only you can save him now.” That brought a telephone call from the Foreign Secretary, Jack Straw, to offer reassurance that that “everything possible” was being done.On Tuesday, Mr Blair, apparently stung by the angry criticism of a family desperate to do “something, anything”, was on the telephone.

He explained the “limitations” on his ability to end their ordeal. But from the Netherlands, Paul Bigley raised the emotional and political temperature, blaming the Prime Minister’s policies in Iraq, calling him a “fibber” and threatening to hound him from office: “If I lose my brother, Blair has to go.”Another brother, Philip, criticised the Prime Minister for appearing at Euston station in London on Monday for the launch of Virgin’s high-speed train service to Manchester. “Mr Blair was posing with Richard Branson over a train that cuts 14 minutes off a journey to London,” he said. “He should have been devoting that time to saving Ken’s life.”The family’s desperation increased with the murder of the second American hostage, Jack Hensley. With would-be mediators apparently unable to contact the kidnappers, the only way of communicating was over TV channels such as al-Jazeera and al-Arabiya On Wednesday, there was a response for the first time. In an 11-minute video posted on the internet, Kenneth appealed directly to the Prime Minister to save him. Not only did it raise the emotional pressure on Downing Street yet further, the kidnappers’ manipulation of their victim prised open a crack between the US and the interim government it had installed in Baghdad.The Iraqi Justice Minister, Malik Dohan al-Hassan, announced on Tuesday that Rihab Taha, known as “Dr Germ”, one of the two women scientists in custody, would be freed on bail.