The fates of a Japanese journalist and Jordanian military pilot are unknown, a day after the latest purported deadline for a possible prisoner swap passed.
"Government institutions are working around the clock on the case of pilot Muath al-Kaseasbeh," Jordanian military spokesman Mamdouh al-Ameri said in a statement.
"We will inform you of any developments in due time."
He urged Jordanians not to listen to rumours.
Jordan has said it will only release an al Qaida prisoner from death row if it gets proof the pilot is alive and so far has received no such evidence from the Islamic State hostage-takers.
Officials in Tokyo also said they had no progress to report.
"There is nothing I can tell you," said government spokesman Yoshihide Suga, reiterating Japan's "strong trust" in the Jordanians to help save the Japanese hostage, freelance journalist Kenji Goto.
Mr Suga said the government was in close contact with Mr Goto's wife, Rinko Jogo, who released a statement late on Thursday pleading for her husband's life.
An audio message purportedly posted online by jihadis said the pilot, Lt Muath al-Kaseasbeh, would be killed if Sajida al-Rishawi, the al Qaida prisoner, was not delivered to the Turkish border by sunset on Thursday, Iraq time.
It was not clear from the recording what would happen to Mr Goto if the Iraqi woman was not turned over by the deadline.
The pilot's father, Safi al-Kaseasbeh, said that he had no word on the fate of his son and had not received any update from Jordanian authorities.
"I have nothing," he said, speaking after Muslim noon prayers in the Jordanian capital of Amman.
With no news on the fate of either the pilot or Mr Goto, their families' agonising wait dragged on.
Jordan faces a tough choice over whether to release al-Rishawi, 44, who faces death by hanging for her role in a suicide bombing, one of three simultaneous attacks on Amman hotels in November 2005 that killed 60 people.
She survived because her belt of explosives didn't detonate. She initially confessed, but later recanted, saying she was an unwilling participant.
She is from the Iraqi city of Ramadi and has close family ties to the Iraqi branch of al Qaida, a precursor of the Islamic State group. Three of her brothers were al Qaida operatives killed in fighting in Iraq.
Releasing al-Rishawi, implicated in the worst terror attack in Jordan, would be at odds with the government's tough stance on Islamic extremism.
However, King Abdullah II faces public pressure to bring home the pilot, who was captured in December after his Jordanian F-16 crashed near the Islamic State group's de facto capital of Raqqa in Syria.
He is the first foreign military pilot to be captured since the US and its allies began airstrikes against the Islamic State more than four months ago.
Jordan's participation in the US-led airstrikes is unpopular in the kingdom, and the pilot is seen by some as a victim of a war they feel the country shouldn't be involved in.