New video of BBC's Johnston

An image of Johnston is projected on TVC

The kidnappers of BBC correspondent Alan Johnston have released a video of him in which he is wearing what he says is an explosives vest.

In the tape, posted on a website used by militants, Johnston says his captors have said they will detonate the vest if force is used to try to free him.

The BBC said in a statement: "It is very distressing for Alan's family and colleagues to see him being threatened in this way. We ask those holding Alan to avoid him being harmed by releasing him immediately. We are keeping his family fully informed and offering them our continued support."

The Gaza correspondent also appeals for a peaceful resolution to his situation, saying talks had reached an advanced stage.

"Captors tell me that very promising negotiations were ruined when the Hamas movement and the British government decided to press for a military solution to this kidnapping," he says.

Hamas leader Ismail Haniya, said Johnston's captivity could not carry on: "We will not allow the continuation of the abduction of the British journalist. The issue of Alan Johnston must end."