The Gaza Strip's second-largest hospital is "completely out of service", a spokesperson for the Gaza health ministry said on Sunday.
It has been reported that there are only four medical staffers currently caring for patients inside the Nasser Hospital in the southern city of Khan Younis.
"The Nasser medical complex is the backbone of healthcare in southern Gaza Strip. Its ceasing to function is a death sentence for hundreds of thousands of Palestinian displaced people in Khan Younis and Rafah," Gaza health minister Ashraf al-Qidra said.
Mr Al-Qidra said a lack of fuel and fighting around the facility had put it out of action.
Nasser was Gaza's largest functioning hospital until Sunday and had been under siege this week in Israel's war with Palestinian militant group Hamas. Israeli forces raided the hospital on Thursday.
Israeli strikes across Gaza overnight into Sunday killed at least 18 people, according to medics and witnesses, as the United States said it would veto another draft UN ceasefire resolution.
The US, Israel's top ally, instead hopes to broker a ceasefire agreement and hostage release between Israel and Hamas, and envisions a wider resolution of the Israeli-Palestinian conflict.
Israeli prime minister Benjamin Netanyahu has pushed back, calling Hamas's demands "delusional" and rejecting US and international calls for a pathway to Palestinian statehood.
Mr Netanyahu has vowed to continue the offensive until "total victory" over Hamas and to expand it to Gaza's southern-most town of Rafah, where more than half the enclave's population of 2.3 million Palestinians have sought refuge from fighting elsewhere.
An air strike in Rafah overnight killed six people, including a woman and three children, and another strike killed five men in the southern city of Khan Younis, the main target of the offensive over the past two months.
