A Japanese hostage held by Islamic State reportedly says they will kill him and a Jordanian pilot within 24 hours if a woman prisoner is not freed.
An image of Kenji Goto in an orange jumpsuit has appeared online along with an audio message purportedly of him pleading for his life.
Journalist Mr Goto, 47, said he has been told this is his last message and that "the barrier to my freedom is the Jordanian government delaying the handing over of Sajida al Rishawi".
He added: "Time is now running very short. It is me for her. What seems to be so difficult to understand?"
In the audio message, Mr Goto purportedly urged the Japanese authorities to put pressure on the Jordanians to release her.
She is in prison for her part in the Amman bombings in 2005 that killed 60 people.
And he said if she was not freed, then he and pilot First Lieutenant Muath al Kasaesbeh would be killed by IS within 24 hours.
Haruna Yukawa, a fellow Japanese hostage of Mr Goto, is believed to have been killed by the Islamist militant group.
It comes after a video purportedly showing an image of Mr Goto holding a picture of a beheaded Mr Yukawa was posted online at the weekend.
