Militants in the Philippines holding workers from the International Committee of the Red Cross say they will kill a hostage on Tuesday if their demands are not met.
Abu Sayyaf militiamen abducted three workers from the Geneva-based agency – a Swiss, an Italian and a woman from the Philippines – in January when the workers were looking at a water project for a jail on the southern island of Jolo.
Albader Parad, commander of the militants, said on Monday that the Philippines military had 24 hours to withdraw from most of the island 950km south of Manila or they would kill one of the hostages at 2pm local time on Tuesday.
In earlier threats the militants said one of the two European hostages would be first.
"Their demands as of last night are physically impossible to comply with," Philippines Interior Secretary Ronaldo Puno said. He hinted that the military would retaliate with "brute force" if any of the hostages were harmed.
Marines and militants last week clashed in a firefight that left several dead. The military later withdrew from a cordon surrounding the militants set up by soldiers in an effort to buy more time.
Last-minute negotiations broke down on Monday, prompting the militants to set a deadline.
"It is impossible to understand what the kidnappers could possibly achieve by hurting [the hostages]," Jakob Kellenberger, ICRC president, said in a statement. "Harming a humanitarian aid worker cannot be justified under any ideology or religious law."
In a press release on Monday, Pope Benedict XVI also called for the release of the hostages.
swissinfo with agencies