U.S. President Joe Biden on Tuesday put off a planned trip to Jordan for talks with Arab leaders, a White House official said, after a deadly blast at a hospital in Gaza signaled an intensification of the war between Israel and Hamas.

Biden was due to visit the Jordanian capital of Amman on Wednesday following a meeting with Israeli Prime Minister Benjamin Netanyahu in Tel Aviv.

Amid rising concern that the conflagration could spiral into a larger regional conflict, the White House on Monday announced Biden would make a short Middle East trip, during which he was initially scheduled to meet with Jordan's King Abdullah, Egyptian President Abdel Fattah el-Sissi and Palestinian President Mahmoud Abbas.

U.S. President Joe Biden waves as he boards Air Force One at Andrews Air Force Base in Maryland on Oct. 17, 2023, en route to Israel. (AP/Kyodo)

But just before Biden's departure, the official confirmed the talks with the Arab leaders had been canceled, a decision taken by Jordan in the wake of the massive explosion in which hundreds of people were killed, with Israel and Hamas blaming each other.

The four-way discussions had to be canceled after Abbas pulled out. Biden is now only visiting Israel.

U.S. officials have said Biden plans to show staunch support for the Jewish state and address the worsening humanitarian crisis in Gaza, a densely populated area ruled by the Palestinian militant group.

The White House said Biden decided to "postpone" his travel to Jordan as Abbas announced three days of mourning after the blast.

The explosion, which has fueled anger across the Arab world, is a further escalation in the war triggered by a sudden attack by Hamas on Oct. 7.

Israeli officials have claimed the deadly hospital incident was due to a failed rocket launch by Islamic Jihad, a smaller and more radical Hamas-aligned armed group. Hamas said the hospital was hit by an Israeli airstrike.

In a message on X, formerly Twitter, U.N. Secretary General Antonio Guterres said he was "horrified" by the killing of Palestinian civilians in what he described as a "strike."

Biden released a statement saying he is "outraged and deeply saddened by the explosion."

Biden said he spoke with the Jordanian king and Netanyahu after hearing the news, and ordered his national security team to continue collecting information about what exactly happened.

In addition to Netanyahu, Biden will meet with the Israeli war cabinet to learn about "the situation on the ground and more critically, their objectives, their plans, their intentions in the days and weeks ahead," according to White House national security spokesman John Kirby.

"He'll be asking some tough questions," Kirby told the press aboard Air Force One. "He'll be asking them as a friend, as a true friend of Israel."

Kirby said Biden is also set to meet with Israeli first responders and families of those who lost loved ones in the Hamas assault, as well as those who still have no information on the fate of their loved ones.

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