The United Nations World Food Program said Tuesday that an aid worker has died in a Yemeni prison three weeks after his detention by Houthi rebels.

The announcement came a day after the U.N. suspended its operations in the rebel's stronghold in northern Yemen.

President Donald Trump will host Jordan's King Abdullah II at the White House on Tuesday as he escalates pressure on the Arab nation to take in refugees from Gaza — perhaps permanently — as part of his audacious plan to remake the Middle East.

The visit is happening at a perilous moment for the ongoing ceasefire in Gaza as Hamas, accusing Israel of violating the truce, has said it is pausing future releases of hostages and as Trump has called for Israel to resume fighting if all those remaining in captivity are not freed by this weekend.

The call came in the middle of the night, Mohammed Shula said. His daughter-in-law, eight months pregnant with her first child, was whispering. There was panic in her voice.

"Help, please," Shula recalled her saying. "You have to save us."

Hamas' threat to delay the next planned release of Israeli hostages from the Gaza Strip has jolted a fragile ceasefire that's seen as having the potential to wind down the war.

The next handover of three hostages had been scheduled for Saturday, and families say time is running out for those still alive. Israel now awaits what comes from a security Cabinet meeting Tuesday morning, moved up in response to Monday's Hamas announcement.

Egyptian President Abdel Fattah al-Sisi urged on Tuesday the reconstruction of Gaza "without displacing Palestinians", after U.S. President Donald Trump said he could "conceivably" halt aid to Egypt and Jordan if they refuse to take in Gazans.

During a phone call with Danish Prime Minister Mette Frederiksen, Sisi "stressed the necessity of starting the reconstruction of the Gaza Strip... without displacing Palestinians and in a way that ensures the preservation of their rights... to live on their land", according to a statement from his office.

The Gaza ceasefire appeared increasingly fragile Tuesday after Hamas said U.S. President Donald Trump's latest warning "further complicates" the agreement with Israel, which has so far led to five hostage-prisoner swaps.

Trump said that "all hell" would break out if Hamas failed to release all Israeli hostages by the weekend.

Saudi Arabia and other Arab countries have condemned remarks by Israel's prime minister who appeared to suggest in an interview that a Palestinian state could be established on Saudi territory.

Egypt announced that it will host an emergency Arab summit on Feb. 27 to discuss "new and dangerous developments" after U.S. President Donald Trump proposed to resettle Palestinians from the Gaza Strip.

Trump's suggestion, made at a White House meeting with Israeli Prime Minister Benjamin Netanyahu last week, infuriated the Arab world, including Egypt, Jordan and Saudi Arabia — key allies of Washington.

New details and growing shock over emaciated hostages have renewed pressure on Israeli Prime Minister Benjamin Netanyahu to extend a fragile Gaza ceasefire beyond the first phase, even as U.S. President Donald Trump repeated his pledge that the U.S. would take control of the Palestinian enclave.

Talks on the second phase, meant to see more hostages released and a complete Israeli withdrawal from Gaza, were due to start Feb. 3. But Israel and Hamas appear to have made little progress, even as Israeli forces withdrew Sunday from a Gaza corridor in the latest commitment to the truce.

U.S. President Donald Trump's plan to take over Gaza will imperil attempts to forge landmark ties between Saudi Arabia and Israel and fuel anti-American sentiment in the oil-rich kingdom, analysts said.

Trump's proposal to redevelop Gaza and oust the more than two million Palestinians living in the territory prompted a global backlash and enraged the Arab world, making it difficult for the Saudis to consider normalisation.