An online message said to be from the Islamic State terror group says a Japanese hostage and Jordanian pilot it holds have less than 24 hours left to live.

The message, posted online, again demanded the release of Sajida al-Rishawi, an Iraqi woman sentenced to death in Jordan for involvement in a 2005 terror attack that killed 60 people.

It also mentioned Jordanian pilot 1st Lt Mu'ath al-Kaseasbeh, who is a captive of IS.

The video which emerged yesterday matched a message released over the weekend, though neither bore the logo of IS's al-Furqan media arm.

The weekend video showed a still photo of Kenji Goto holding what appears to be a photo of the body of Japanese hostage Haruna Yukawa.

The new message says that unless the Jordanian government frees Ms al-Rishawi within 24 hours, Mr Goto and the pilot will be killed, adding that this would be the group's last message.

The message warns any delaying tactics by the government will result in the death of both men.

Mr Goto has only "24 hours left to live and the pilot has even less," the message said.

A Japanese envoy in Jordan, Deputy Foreign Minister Yasuhide Nakayama, had earlier expressed hope the two hostages would return home "with a smile on their faces".

"I hope we can all firmly work hard and join hands to cooperate, and for the two countries (Japan and Jordan) to cooperate, in order for us to see the day when the Jordanian pilot and our Japanese national Mr Goto, can both safely return to their own countries with a smile on their faces," he told reporters late on Monday night after another day of crisis talks in the Jordanian capital.

Japanese officials later held emergency meetings after the video's release while officials in Jordan were also investigating the new message.

Government spokesman Yoshihide Suga said he had seen the latest video released, but did not comment on its authenticity.

"In this extremely tough situation, we are continuing as before to request the cooperation of the Jordanian government to work toward the immediate release of Mr Goto," Mr Suga said.