An Iraqi group purportedly holding two French journalists hostage has demanded a $5 million (€4.1 million) ransom and set a 48-hour deadline for their demands to be met.
A statement, posted on a Web site in the name of the Islamic Army in Iraq, punctured the mood of cautious optimism in France that reporters Christian Chesnot and Georges Malbrunot would soon be free.
The kidnappers' statement, which could not immediately be authenticated, said the group had previously planned to release the men but that attacks on them had prevented from doing so.
They did not elaborate.
A group with the same name previously sent videotaped messages to the satellite television station Al Jazeera showing the two men. The French Foreign Ministry declined to comment on Monday's statement.
The ransom demand and fresh deadline were the first word from the kidnappers since a previous ultimatum expired last Wednesday.
Today's statement also called for a truce with al Qaeda leader Osama bin Laden and a promise of no military and commercial dealings with Iraq - demands which appeared to be directed at France.
The group said it would accept just one of its demands being met, but issued a warning against any attempt to attack it: "We warn you not to bombard us as you did ... on the day when we intended to deliver them (the hostages) to you."
The Islamic Army in Iraq stunned France when it seized the men and demanded the Paris government revoke a law banning Muslim headscarves in state schools. France refused the demands and the law went into force last Thursday.
Last week French officials suggested its nationals were no longer in the hands of their original captors and had been turned over to an Iraqi group opposed to the US-backed Iraqi authorities in Baghdad.
The ransom demand was a blow to hopes of a swift resolution of the dragging hostage crisis, which triggered an unprecedented expression of support from the Arab world, Islamic religious figures and French Muslim groups.
A French Muslim leader who travelled to Iraq to try to secure their freedom said earlier on today that talks on their release were in the "delivery phase", but that a surge of violence in Iraq has complicated the situation.
"I think we are in a phase that is a phase I would call the delivery of the hostages, which is different to the phase of releasing the hostages," Fouad Alaoui, secretary-general of the Union of French Islamic Organisations, told Europe 1 radio.
"I am of the view that the hostages are no longer in the hands of their first kidnappers but rather in the hands of the Iraqi resistance," said Alaoui.
He was speaking in France after travelling to Iraq with Muslim leaders to try to win the release of the men, captured between Baghdad and Najaf on August 20.
Muslim leaders who were in Baghdad say new US military operations in Iraq and insurgent attacks may have made it harder to arrange a safe handover.
Regretting violence amid new US military operations in Iraq, Alaoui said: "I think that is making the mission difficult."
By Friday, government officials said they were hopeful the journalists would be released but since then they have grown more cautious.
Defence Minister Michele Alliot-Marie told LCI television: "This country (Iraq) is in complete chaos, so that poses major difficulties.
"All we can say today is that we have reliable indications that allow us to think they are in good health and that (their) release is possible."
A religious edict or fatwa was announced yesterday by a hardline Sunni Muslim cleric, Sheikh Mehdi al-Sumaidaie, ordering the release of Chesnot and Malbrunot.
Scores of hostages from dozens of countries have been seized in the past five months, and more than 20 have been killed, as part of a campaign to undermine Iraq's interim government.