The World Health Organization said it delivered much-needed aid and supplies to Al-Shifa Hospital in northern Gaza and the Palestine Red Crescent Society's Al-Amal Hospital in southern Gaza on Tuesday.

Al-Shifa and Al-Amal hospitals are also operating as shelters for displaced residents, sheltering 50,000 people and 14,000 people respectively, according to the WHO.

Gaza has 13 partially functioning hospitals, two minimally functioning hospitals and 21 hospitals that are not functioning at all, causing the hospitals that are functioning to become overloaded with patients who need help, according to the WHO.

"Today I repeat my call on the international community to take urgent steps to alleviate the grave peril facing the population of Gaza and jeopardizing the ability of humanitarian workers to help people with terrible injuries, acute hunger, and at severe risk of disease," WHO Director-General Dr. Tedros Adhanom Ghebreyesus said in a statement.

Tedros said a cease-fire is needed "to spare civilians from further violence and begin the long road towards reconstruction and peace."

Twenty people have been killed in a strike on a building near the Red Cross Al-Amal Hospital in Khan Younis in southern Gaza, according the Hamas-run Gaza Ministry of Health. The death toll is likely to rise, the Gaza Ministry of Health said.

-ABC News Nasser Atta

At least 241 people have been killed in Gaza in a 24-hour period, according to the Hamas-run Gaza Ministry of Health.

This comes as Israeli forces expand their ground offensive to central Gaza, launching over 200 rockets in one day, according to the Gaza Ministry of Health.

Secretary of State Antony Blinken and National Security Adviser Jake Sullivan met with Israeli Minister for Strategic Affairs Ron Dermer Tuesday night, where they discussed freeing hostages still held in Gaza.

During the meeting, they covered four key points, officials familiar with the meeting told ABC News, including the transition to a different phase of the war to maximize Israel's focus on precision targeting of high value Hamas targets. They also worked on practical steps to improve the humanitarian situation and minimize harm to civilians. Planning for after the war ends was also covered, with discussions about governance and security in Gaza, a political horizon for the Palestinian people and continued work on normalization and integration.

The meeting came on the same day President Joe Biden spoke by phone with Qatar's Amir Sheikh Tamim Bin Hamad Al-Thani. According to a read-out of the call, the two leaders spoke about the efforts to see hostages released and ongoing efforts to get more humanitarian aid into Gaza.

-ABC News' Lauren Peller and Jay O'Brien

Gadi Hagi, a 73-year-old American-Israeli hostage and member of Kibbutz Nir Oz, has been confirmed dead, the kibbutz said.

Hagi was killed on Oct. 7 at the kibbutz and his body was taken to Gaza where it's still being held, according to a kibbutz spokesperson.

Hagi’s wife, 70-year-old Judy Weinstein, is wounded and still being held hostage, the kibbutz said.

Hagi and his wife were shot and kidnapped on Oct. 7, according to the Hostage Center.

"Gadi was a man full of humor who knew how to make those around him laugh," the Hostage Center said in a statement. "A musician at heart, a gifted flautist, he played in the IDF Orchestra and was involved with music his whole life."

Hagi was a father of four and a grandfather of seven.

Hagi reportedly has ties to New York.

"May Gadi's memory be a blessing," New York Gov. Kathy Hochul wrote on social media. "There are still many hostages -- including many with New York connections -- being held in Hamas captivity."

President Joe Biden said he was "heartbroken by the news."

"We continue to pray for the well-being and safe return of his wife, Judy," Biden said in a statement. "We are praying for their four children, seven grandchildren, and other loved ones and are grieving this tragic news with them."

Biden said Hagi's daughter joined, via phone, his meeting last week with families of hostages.

"Those families bravely shared with me the harrowing ordeal that they have endured over the past months as they await news of their loved ones," Biden said. "I reaffirm the pledge we have made to all the families of those still held hostage: we will not stop working to bring them home."