Japan’s negotiations with the Islamic State group, who are threatening to execute a Japanese journalist and a Jordanian pilot, have become “deadlocked,” Japan’s deputy foreign minister said, according to a local media report on Saturday. ISIS is seeking the release of Sajida al-Rishawi, a female suicide bomber who attacked a hotel in Jordan in 2005, for the lives of Kenji Goto and Muath al-Kaseasbeh.

Yasuhide Nakayama, who is leading the country’s emergency response team in Amman, reportedly said late Friday that there has been no progress in trying to secure the release of Goto and al-Kaseasbeh, and that authorities are waiting for information on the two held by the Sunni militant group. Japan has been working with Jordan for the safe release of the two hostages, while Jordan has demanded evidence from ISIS that the pilot is still alive before it releases al-Rishawi.

"It has become deadlocked," Nakayama said, according to Japan's public broadcaster NHK. "Staying vigilant, we will continue analyzing and examining information as the government is making concerted efforts together."

Jordan has offered to release al-Rishawi if ISIS releases the pilot, who crashed in Syria on Dec. 24. Officials, speaking on the condition of anonymity, told the New York Times on Thursday that al-Rishawi would remain jailed in Jordan as long as there was no proof al-Kaseasbeh was still alive. Authorities are unaware of the situation of Goto and al-Kaseasbeh after the deadline for a swap passed Thursday. However, since then there has been no news from ISIS regarding the hostages.

In its most recent message, ISIS extended its deadline for the release of al-Rishawi, stating that the Iraqi woman should be present at the Turkish border by sunset Thursday, or al-Kaseasbeh will be killed.

The Jordanian government has been under heavy pressure to secure the release of its military pilot as well as the Japanese journalist, whose life was threatened by ISIS during the first video released by the group last week. In the video ISIS threatened to kill Goto and another Japanese hostage Haruna Yukawa, who was captured in Syria last August. In another video last Saturday, ISIS announced the execution of Yukawa after a 72-hour deadline to pay a ransom of $200 million passed.