An estimated 220,000 Palestinians are sheltering throughout 92 United Nations relief and refugee facilities Refugees facilities across the Gaza Strip, according to U.N. Secretary-General Antonio Guterres.

Guterres called for "rapid and unimpeded humanitarian access now," early Thursday morning, local time.

Hospitals in Gaza are working at full capacity and have run out of space for those "wounded from Israeli airstrikes" to be treated, the Palestinian-Gaza Strip Ministry of Health said in a press release Wednesday.

The Ministry called for urgent action to be taken to provide safe passage for medical supplies and to transfer the wounded. Health services have reached a critical stage, according to the release, with "medicines, medical consumables and fuel" expected to run out imminently.

An Israel Defense Forces spokesperson addressed a possible ground incursion in an interview with David Muir, as the "World News Tonight" anchor reports from Israel.

IDF Lt. Col. Jonathan Conricus told Muir Wednesday that the "carnage" in the kibbutz of Be'eri, where more than 100 bodies were found, "definitely put things into perspective."

Following Hamas' attack, 360,000 Israeli reservists have been called up and tanks and soldiers are amassing on the Gaza border.

"One could deduce that from the troops that we have called up that it is what they will be tasked to do," Conricus told Muir, adding that at the end of the war, Hamas "won't have the military ability to kill or hurt Israeli civilians ever again."

Asked whether there was any scenario where a ground incursion would not happen, Conricus responded that it's "difficult to say."

"I personally don't think so. But that matters less," he said. "Our job is to be prepared and have all the troops ready for whatever assignment and however it is decided to implement them."

Two U.S. officials familiar with the diplomatic efforts to free hostages told ABC News it appears that allies and partners in the Middle East in communication with Hamas are being helpful in advocating for their release.

The officials say Hamas has shown no real willingness to partake in diplomacy up to this point.

Hamas’ designation as a foreign terrorist organization also complicates any negotiations involving the U.S., because the official label makes it illegal for any American to knowingly provide "material support or resources," which includes personnel.

Deputy Special Envoy for Hostage Affairs Steve Gillen is among the U.S. delegation en route to Israel with the Secretary of State Antony Blinken.

In remarks earlier Wednesday, President Joe Biden said "there's a lot we're doing" to bring the hostages home.

"In the days ahead we're gonna continue to work closely with our partners in Israel and around the world,” he said.

-ABC News' Shannon K. Crawford

A State Department official said Monday night that the department has offered 4,000 American citizens and their immediate family members help to depart Israel via government-organized transportation since Friday.

“Since Oct. 13, we have augmented the limited commercial flight availability by offering more than 4,000 seats on U.S. government-chartered transport by air and sea to U.S. citizens and their immediate family members,” one official said. “We have communicated the availability of departure assistance options for U.S. citizens via targeted, individualized messaging as well as via broad public messaging.”

Departing flights, though, were not nearly at capacity, the official said.

“The departure options we have offered have generally departed at half capacity or less. Nearly 1,000 U.S. citizens and their immediate family members have departed on U.S. government-chartered transport,” an official said.

The official added that 3,000 other American citizens have told the State Department that they were able to leave Israel and the West Bank on their own.

-ABC News’ Shannon Crawford