Japan on Thursday said a fresh message from ISIL terrorists threatening to kill Japanese and Jordanian hostages was very likely genuine.

Japan on Thursday said a fresh message from ISIL terrorists threatening to kill Japanese and Jordanian hostages was very likely genuine.

Chief Cabinet Secretary Yoshihide Suga told journalists the recording, which demands the release of a failed suicide bomber, seemed real. "We are in the process of confirming it but it is highly probable that the voice is (Kenji) Goto's," he said.

Tokyo is pleading with Amman to help rescue Goto, a journalist who was taken hostage by ISIL.

In their new message posted early Thursday, the militants demanded that Amman hand over by "sunset" female terrorist Sajida al-Rishawi, who is on death row in Jordan for her role in 2006 triple hotel bombings in Amman that killed 60 people.

Suga said that Japanese Prime Minister Shinzo Abe had asked "various countries, including Turkey... for their cooperation".

The recording, in English, says the Jordanians must present Sajida al-Rishawi at the Turkish border by sunset Thursday, or Jordanian pilot Mu'as al-Kasaseabeh will be killed.