US President-elect Donald Trump has called for the release of the hostages being held in the Gaza Strip. He has also suggested that the people involved in their capture will pay a heavy price, if the hostages are not freed before he is inaugurated in January.

More than 40,000 people have been killed in Gaza since Israel launched its military operation in the enclave more than one year ago.

Meanwhile, about 100 hostages, including people who have US citizenship, are still being held in Gaza by the Islamic group Hamas. Negotiations aimed at bringing about a ceasefire and securing the release of the hostages remain stalled.

Trump posted a message on social media on Monday. He said, "If the hostages are not released prior to January 20, 2025, the date that I proudly assume Office as President of the United States, there will be ALL HELL TO PAY in the Middle East, and for those in charge who perpetrated these atrocities against Humanity."

He added, "Those responsible will be hit harder than anybody has been hit in the long and storied History of the United States of America."

Trump's move comes after Hamas released a video of a man it says is a hostage. The video was released last Saturday.

The man, who is believed to be an American-Israeli citizen, urged Trump to engage in negotiations aimed at securing the release of the hostages.