Brushing aside a decision by Baghdad's Justice Ministry that biological weapons scientist Rihab Taha could be freed, interim Prime Minister Iyad Allawi released a statement on Thursday that said he was not willing to sanction her release "at this time".
His decision comes less than 24 hours after the US embassy in Baghdad said it would not permit the release of two other women in the "physical custody of the multinational forces in Iraq".
But an Iraqi group that has executed two American captives and is threatening to kill a Briton captured with them, Kenneth Bigley, are demanding the immediate release of all Iraqi women in US detention in Iraq.
The government statement responded that "there is no question of the Iraqi government ... changing these decisions in the light of the demands of a terrorist group which has taken three hostages and criminally and barbarically murdered two of them".
Bigley's brother reacted to the Iraqi PM's statement with disbelief and accused the US-led forces in Iraq of having "sabotaged" his safe release.
Paul Bigley told a British radio station that there had been "a shadow of light in a big, long, dark, damp, filthy, cold tunnel" when an Iraqi judge on Wednesday approved the release of the woman scientist, as demanded by his brother's abductors.
Kenneth Bigley has called on
British PM Blair to save his life
"All the [foreign] powers have to do now is allow the Iraqis to conduct their own internal affairs the way they should be doing."
He continued: "A judge [in Iraq] has made a legal decision to release three people, one female and two males. The minister of justice has endorsed this [and] published this on international news.
"Now this has been sabotaged. I mean ... is this a puppet government, or are the Americans moving the goalposts to suit their own means again? What's going on here? Leave the Iraqis to do their own Iraqi business."
According to an Iraqi political analyst, the PM's decision to overrule the ministry of justice further underlines the total lack of a real Iraqi policy or government.
Nizar al-Samarai adds that interim Minister of State Qasim Dawud had previously announced Dr Taha's custody was unjustified and her release posed no danger to Iraqi national security.
Baghdad had earlier said weapons
scientist Rihab Taha would be freed
"The US Administration says Dr Taha has carried out some tests on Weapons of Mass Destruction (WMD), despite the US forces' failure to find any evidence ... even after 18 months of occupation," he said.
"The Iraqi government is obliged to release her even if there were no hostage crisis, but it is US ambassador Negroponte that is limiting Iraq's ability to deal with this problem."
On Wednesday, a terrified Kenneth Bigley made an emotional appeal to British Prime Minister Tony Blair to save his life.
"I need you [Blair] to be compassionate as you always said you were ... I don't want to die," said the hostage, breaking into tears, in a poor quality video posted on the internet.
The captive crisis has had a deep impact on some Britons. One London-based student, Jenny Black, even contacted Aljazeera.net to say she was willing to travel to Iraq and negotiate with the al-Tawhid and al-Jihad captors in person.
"In return for releasing Kenneth Bigley, we would promise to step up public pressure on Tony Blair and his illegal decision to take this country into a war it did not want. We would organise a media campaign," she said.