A group led by Al Qaida ally Abu Musab Al Zarqawi appealed to Iraqi militants holding an Iraqi-British aid worker to free her unless she was proven to be a spy, a message posted on an Islamic web site said.
The unknown militant group holding Margaret Hassan, director of Care International's now halted operations in Iraq, has threatened to turn her over to Al Zarqawi's group unless British troops quit Iraq.
"We call on those responsible for her abduction to free her ... unless there is proof of her being an agent," Zarqawi's group said in the message.
It said the captors were obligated to publish any evidence they might hold against her. The message could not be immediately authenticated.
"Those who use this hostage like a playing card have not understood our religion well," the message said. "We announce to the whole world that if they hand over this hostage to us we would release her immediately unless it is proven that she plotted against Muslims," it added.
Al Zarqawi's Al Qaida organisation in Iraq has claimed responsibility for hostage beheadings and some of Iraq's bloodiest suicide attacks.
Dublin-born Hassan, who was seized in Baghdad on October 19, has an Iraqi husband and has lived in Iraq for 30 years. She holds British and Iraqi passports.
Militants have waged a campaign of kidnappings and killings to try to force US-led troops and foreigners to leave Iraq.
