A Japanese journalist held hostage by Islamic State says he and a captured Jordanian pilot will be killed today unless their kidnappers' demands are met.

In an online message, Kenji Goto claims IS militants will only spare their lives if Jordan frees an Iraqi woman sentenced to death over a suicide bombing.

Japan's Prime Minister's described the video as 'despicable'.

Safi al-Kaseasbeh - the father of the pilot - says the Jordanian authorities should accept the request.