The U.S. government on Saturday advised its citizens in Gaza to move south toward the Rafah border crossing with Egypt to be ready for its possible reopening amid the humanitarian crisis in the coastal enclave after a Hamas attack in Israel drew Israeli military retaliation.

Washington worked with Egypt, Israel, and Qatar to try to open the Rafah crossing for limited hours on Saturday afternoon to allow Palestinian-Americans to leave, a senior State Department official told reporters traveling with Secretary of State Antony Blinken.

But it was unclear whether Hamas, which controls Gaza, would allow access to the crossing, or whether any U.S. citizens were able to exit, the official said later. It was not immediately known whether the U.S. would make another attempt to get Rafah opened on Sunday.

"We have informed U.S. citizens in Gaza with whom we are in contact that if they assess it to be safe, they may wish to move closer to the Rafah border crossing," a U.S. State Department spokesperson said. "There may be very little notice if the crossing opens and it may only open for a limited time."

The U.S. government estimates the number of dual-citizen Palestinian-Americans in Gaza at 500 to 600 among the strip's population of 2.3 million, and Washington hopes to get many of its nationals out of harm's way.

On the third day of his most extensive trip yet to the Middle East, Blinken met with Saudi Foreign Minister Prince Faisal Bin Farhan in Riyadh as the top American diplomat works with regional allies to prevent the war between Israel and Hamas from spiraling into a bigger conflict and to help secure the release of hostages kidnapped by the terrorist group.

With Washington especially determined to deter Iran from becoming involved, Blinken also spoke by phone with China's foreign minister, Wang Yi. He asked his Chinese counterpart to help keep the conflict from spreading, State Department spokesperson Matthew Miller said.

It was the first high-level contact between Washington and Beijing since last weekend's Hamas attack and came amid heightened tensions between the two rival powers on a range of issues.

Working to Protect Civilians

Blinken started his tour in Israel where he voiced U.S. support for Washington's closest Middle East ally in its war against Hamas, whose gunmen rampaged through Israeli towns on Oct. 7, killing 1,300 people and taking dozens of hostages into Gaza. Israeli's military retaliation has killed more than 2,200 people, according to authorities in Gaza, and leveled whole neighborhoods.

Speaking before the meeting in Riyadh, Blinken said protecting civilians on both sides of the conflict was vital.

"And we're working together to do exactly that, in particular working on establishing safe areas in Gaza, working on establishing corridors so that humanitarian assistance can reach people who need it.

"None of us want to see suffering by civilians on any side, whether it's in Israel, whether it's in Gaza, whether it's anywhere else. And we're working together to do our best to protect them," Blinken said.

In remarks published by the U.S. State Department, the Saudi foreign minister said the priority had to be stopping further civilian suffering.

"I have to emphasize that the humanitarian situation in Gaza is very, very difficult. And we need to work together to make sure that access for humanitarian relief and humanitarian goods is allowed," the minister said.

After his meeting in Riyadh, Blinken traveled to the United Arab Emirates to meet President Sheikh Mohammed bin Zayed Al Nahyan.

Blinken's call earlier with his Chinese counterpart was "productive," Miller said. The Chinese, he added, "do have influence with a number of countries in the region."

China's foreign ministry said in a statement that Wang called for an international peace conference over the crisis and that the two men also touched on U.S.-China relations, which Wang said were showing signs of stabilizing.

Biden was due to return to Riyadh later on Saturday and may meet with Saudi Crown Prince Mohammed bin Salman. He is scheduled to fly to Egypt on Sunday before returning to Washington.