The United States, Egypt and Israel are in talks to reopen the crossing — also vital for aid deliveries to the Strip — though little progress has been made. The Israeli rights group Gisha said it successfully lobbied for 18 Palestinian citizens of Israel and residents of Jerusalem to leave Gaza in late May through Kerem Shalom, another southern crossing.

But Israel’s offensive in Rafah, aimed at eliminating Hamas’s last battalions, has dashed any hope of escape for the rest of Gaza’s ill and injured civilians, as the health system collapses and the U.N. warns that more than a million people could face starvation by mid-July. For some, the border closure has already been a death sentence.

Fidaa Ghanem, 44, was diagnosed with lymphoma in late February; she and husband Maher, 46, had at first attributed her weight loss to war stress and food shortages.

The radiotherapy and chemotherapy Fidaa needed was not available in Gaza, Maher said, so doctors referred her for medical treatment abroad. By mid-March, he secured financial support from the Ramallah-based Palestinian Ministry of Health for treatment in Egypt, according to a document the family shared with The Post.

Fidaa’s name was on a list of approved departures for May 7, the day after Israeli tanks rolled into Rafah and seized the crossing.

“My wife was deprived of traveling and receiving treatment in Egypt,” Maher said.

Fidaa spent her last weeks at al-Aqsa Hospital in Deir al-Balah, now Gaza’s largest functioning hospital, though there was little they could do, according to her husband.

“Her health condition is deteriorating and the tumor is spreading,” he told The Post on May 31. “There is no medical care, even the painkillers that are given [to her] are weak and not sufficient for a cancer patient.”

The mother of five passed away on June 4.

The World Health Organization estimated on June 7 that 14,000 people in Gaza need to be evacuated for medical treatment. COGAT, the Israeli agency that controls movement in and out of the enclave, did not immediately respond to a request for comment on Fidaa’s case, or on whether it planned to provide an alternative exit route for other sick and wounded Palestinians.

More than 37,000 people have been killed and nearly 85,000 injured in eight months of war, according to the Gaza Health Ministry, which does not distinguish between combatants and civilians but says the majority of the dead are women and children.

Even when Rafah was open, permissions to cross were hard to come by. As of May 14, Israeli authorities had received 12,760 requests for Palestinians to leave for medical treatment and approved 5,857, or 46 percent, according to Bisma Akbar, a communications officer for the WHO, which works with the Gaza Ministry of Health to facilitate requests.

Men between the ages of 19 and 60 were the most likely have their applications denied, according to the WHO figures. Abdullah Abu Sobeih, 40, was among those unable to leave.

He was paralyzed in March, he told The Post by phone, when a sniper shot hit his spinal cord as he was pulling the bodies of dead relatives from the rubble of a strike in southern Gaza. He received a medical referral from the International Medical Corps Hospital in Khan Younis and had hoped to travel in mid-April, he said, but his name never appeared on the list of those approved to transit through Rafah.

COGAT did not respond to questions about Abu Sobeih’s case.

The father of three has since been confined to diapers at a field hospital in the south.

“All they can do is deal with the ulcers that appeared on my back and buttocks due to my inability to move,” he said.

Israeli military officials described the seizure of the Rafah crossing as essential for cutting off Hamas’s “oxygen line,” used by the group to smuggle in weapons and evacuate injured fighters.

But it was also a way out for desperate civilians, even those without serious medical conditions. As of April, about 100,000 Palestinians had left Gaza for Egypt, according to Diab al-Louh, the Palestinian Authority’s ambassador in Cairo.

Many fundraised online and pooled their life savings to apply to leave through Hala Consulting and Tourism, an Egyptian company that reportedly has close ties to the country’s security services.

Hala charged a “coordination” fee — averaging about $5,000 per adult and $2,500 per child, astronomical sums in Gaza — to register names on the Egyptian list of people approved to enter. Typically, Palestinians were required to have a relative pay in person at Cairo’s Hala offices in U.S. dollars, despite a foreign currency crunch in Egypt.

Israeli officials still had a final say over who was permitted to exit the Strip.

Diaa Rashwan, head of Egypt’s State Information Service, released a statement in January condemning “false allegations” that the government was involved in charging Palestinians to exit Gaza. In March, Egyptian foreign minister Sameh Shoukry told Sky News his country “absolutely [did] not” condone Hala’s practices.

The government “is already looking into it and will take action vis-à-vis anyone who has been implicated in such activities,” he said.

Hala did not respond to a request for comment.

Before the Rafah crossing was closed, families who had applied would closely watch the company’s posts on social media to see who had been approved to leave the next day.

Families who completed the complex and costly process are now in a new kind of limbo.

Khalil al-Khatib’s home in Rafah was hit by an airstrike early in the war, killing his mother and brother and badly wounding his sister, who was evacuated to Egypt for medical treatment.

In mid-April, as Israel’s offensive on Rafah loomed, Khatib paid $17,500 to register himself, his wife and three children with Hala. His family fled to Deir al-Balah, in central Gaza, before fighting began, but had planned to return to Rafah and make it into Egypt.

“Instead of traveling, I am now only searching for safety,” he said.

He could apply to Hala for a refund, but doesn’t want to risk losing his place in line “in the hope that the crossing will be reopened.”

For some, like Mohammad Abu Ataya, 35, it is already too late.

His youngest son, Fayez, was born in early December in the Nuseirat refugee camp, “an area that witnessed very violent raids and fire belts,” he said, referring to repeated Israeli strikes on a single location. The family of six was displaced five times. After each attack, Fayez inhaled dust, debris and other toxins, Mohammad said.

The baby developed a persistent cough and fever. Doctors found a cyst on his collapsed right lung, according to medical records viewed by The Post. In mid-May, doctors at the European Hospital in Khan Younis operated on Fayez; his father hoped to secure a medical referral abroad for him as he recovered from surgery, he said.

The baby was released from the overcrowded hospital and the family returned to their tent in Rafah but was soon on the run again — fleeing to Mawasi, a coastal area designated by Israel as a humanitarian zone. They struggled to stay in touch with Fayez’s doctors in Khan Younis and, with the border closed, they could no longer find the fortified powdered milk he needed. He began to lose weight.

On May 30, Mohammed awoke to find Fayez limp and unresponsive. It took nearly two hours to reach a hospital, he said, where Fayez was declared dead on arrival.

He was not yet six months old.

Harb reported from London. Hazem Balousha and Claire Parker contributed reporting from Cairo.