London: British Foreign Secretary Jack Straw appealed on Thursday to the kidnappers of four Westerners in Iraq to get in contact, and called again for their release.

Straw made his appeal to the kidnappers - which did not include an explicit offer to open negotiations - next to the Christmas tree outside the front door of Downing Street before a meeting of Prime Minister Tony Blair's cabinet.

The group holding the four Westerners on Wednesday extended by 48 hours a deadline to kill them unless Iraqi detainees are freed.

"As I've said before, if the kidnappers want to get in touch with us, we want to hear what they have to say. We have people in Iraq itself and in the region and they are ready to hear from the kidnappers," Straw told reporters.

"Norman Kember and his colleagues are campaigners for peace dedicated to help others. We ask for their release," he said.

Straw's statement came after international media broadcast what they said was a new video of the hostages, showing Kember and another hostage wearing orange jumpsuits and blindfolds and with their hands shackled together.

Other hostages have been dressed in orange jump suits prior to execution. The jump suits are typical of US jails and associated around the world with images of Muslims detained at Guantanamo Bay.