The World Health Organization described the destruction in Khan Younis as "disproportionate to anything one can imagine."

Nasser Medical Complex -- once the "backbone" of the health system in southern Gaza -- Al-Amal and Al-Khair hospitals are "non-functional," according to WHO Director-General Tedros Adhanom Ghebreyesus.

"These facilities have no oxygen supply, water, electricity or sewage system," he said Thursday on X, a day after WHO team members and partners went to Khan Younis to assess health facilities following the withdrawal of Israeli troops from the city.

Jordanian Field Hospital was found to be "minimally operational," he said.

"The once robust health system in Gaza is broken," Ghebreyesus said. "WHO and partners stand ready to support reconstruction and rehabilitation efforts, but we need a ceasefire. Nothing else can bring a lasting and humane outcome."

Israeli military spokesman Rear Adm. Daniel Hagari told reporters Thursday that Israel is constructing a new land crossing from Israel into northern Gaza to facilitate more aid deliveries.

The Erez crossing, a key pedestrian crossing that was destroyed by Hamas on Oct. 7, will remain closed.

Last week, Israeli Prime Minister Benjamin Netanyahu said he would reopen the crossing for aid after speaking with President Joe Biden following the deaths of seven World Central Kitchen workers by an Israeli airstrike.

Although the timetable for the opening of the new land crossing wasn't revealed, Hagari said it would be located near the Erez crossing but not in the exact same spot.

Hagari said he expected 58 trucks would pass through the new crossing daily.

-ABC News' Will Gretsky

Following USAID Administrator Samantha Power acknowledging that famine is happening in northern Gaza, the White House was pressed Thursday on whether this could have been prevented if they had pressured Israeli Prime Minister Benjamin Netanyahu sooner to increase deliveries of humanitarian aid.

The U.S. has often called on Israel to open more crossings and allow for more aid to reach Gaza, but it wasn't until last week when President Joe Biden told Netanyahu that U.S. policy on Gaza hinges on Israel announcing and implementing measurable steps to address civilian harm, humanitarian suffering and the safety of aid workers.

"Every time the president has spoken to the prime minister there's -- part of that conversation has been to do more humanitarian aid," White House press secretary Karine Jean-Pierre said when asked if it was a mistake not to push Netanyahu to open the Ashdod port and Erez crossing sooner to help prevent famine.

She was asked specifically who is to blame for famine in Gaza, but she didn't attribute it to anyone, instead saying the focus is going to be on getting aid in.

"The humanitarian situation in Gaza, obviously, is dire. And that is why the president is doing everything that he can to get more humanitarian aid in," she said. "And that's what our focus is going to be."

-ABC News' Justin R. Gomez

The State Department revealed that U.S. government employees and their family members are now prohibited from undertaking any personal travel in Israel outside of the greater Tel Aviv, Jerusalem and Be’er Sheva areas "until further notice."

The alert says the restrictions were imposed "out of an abundance of caution" and shared to help other Americans in Israel make their own security plans.

"In response to security incidents and without advance notice, the U.S. Embassy may further restrict or prohibit U.S. government employees and their family members from traveling to certain areas of Israel (including the Old City of Jerusalem) and the West Bank," the alert adds.

Asked whether the limitations were directly connected to Iran’s threats, State Department spokesperson Matthew Miller declined to speak to the specific assessments motivating the policy but acknowledged the public warnings from Iran and said Israel is in "a very tough neighborhood."

"Clearly we are monitoring the threat environment in the Middle East and specifically in Israel, and that's what led us to give that warning to our employees and their family members and to make it public so all U.S. citizens who either live in Israel or traveling there are aware of it," he said.

-ABC News' Shannon Crawford

Iran has launched dozens of drones toward Israel, but it could take hours for them to reach, according to Israel Defense Forces spokesperson Daniel Hagari.

Israel is closing down its airspace after midnight local time and Israel's defense systems are deployed, according to Prime Minister Benjamin Netanyahu.

"We are prepared for any scenario, both in defense and attack," Netanyahu said in a video statement.

"The IDF is on high alert and is constantly monitoring the operational situation. The IDF Aerial Defense Array is on high alert, along with IAF fighter jets and Israeli Navy vessels that are on a defense mission in Israeli airspace. The IDF is monitoring all targets," the IDF said in a statement.

"We ask the public to adhere to and follow the instructions of the Home Front Command and the official IDF announcements regarding the matter," the statement added.