The Israeli prime minister, Benjamin Netanyahu, has convened a security cabinet expected to be held on Thursday evening to discuss the full occupation of the Gaza Strip, which aid agencies have warned would lead to countless more Palestinian deaths and further mass displacement.

The families of the roughly 20 remaining living hostages have called for Israelis to protest against the government and a decision they fear would endanger the lives of their loved ones.

On Thursday morning, about 20 family members of those still held captive in Gaza boarded about 10 boats that departed from the coastal city of Ashkelon, near the border with Gaza, carrying yellow flags and posters bearing the images of the hostages, as they shouted their names.

Families holding pictures of their loved ones and calling for the immediate release of the hostages, during the flotilla near Ashkelon. Photograph: Abir Sultan/EPA

Speaking in English through a megaphone, Yehuda Cohen, whose son, Nimrod, was captured by Hamas on 7 October 2023, said: “Mayday, mayday, mayday. We need all international assistance to rescue the 50 hostages who are nearly two years held by the hand of Hamas.”

“Please, we need international help,” Cohen added.

Of the 251 people kidnapped on 7 October by Hamas and its allies, 49 remain hostages in Gaza, of whom 27 have been declared dead by the army.

“This is the moment for courageous leadership,” the families said, appealing directly to Netanyahu, as well as the lead hostage negotiator, Ron Dermer, and the IDF chief. “Continued obstruction, delay, and failure to bring our loved ones home will be a tragedy for generations. The responsibility is yours. Do not sacrifice our loved ones on the altar of an endless war.”

Israeli media, citing officials speaking on condition of anonymity, said Netanyahu was hoping to seek approval on the full occupation of Gaza.

The plan would mean sending ground troops into the few areas of the strip that have not been totally destroyed, roughly 25% of the territory where much of its 2 million people have sought refuge.

Protesters urged Netanyahu to show ‘courageous leadership’ and end the war. Photograph: Debbie Hill/UPI/Shutterstock

Israel is reportedly preparing a two-phase operation aimed at seizing control of Gaza City, with plans to evacuate about a million residents – half of Gaza’s population – in what officials describe as a temporary measure to establish civilian infrastructure in central Gaza.

According to Israel’s Channel 12, the campaign is being framed as a limited operation rather than a full invasion, apparently to placate military chiefs wary of long-term occupation. The chief of staff, Lt Gen Eyal Zamir, is said to have warned that occupying Gaza would plunge Israel into a “black hole” of prolonged insurgency, humanitarian responsibility and heightened risk to hostages.

The operation’s goal – potentially involving up to five IDF divisions and lasting four to five months – suggests a far more extensive campaign. Israeli officials say the campaign aims to pressure Hamas back into negotiations, and possibly align with a broader US-led peace framework.

Yet many remain sceptical. As one unnamed security official put it: “We are entering a Vietnam model, with our eyes wide open.”

Netanyahu is under intense international pressure to reach a ceasefire agreement, but he also faces internal pressure from within his coalition to continue the war. Some far-right allies in his government have pushed for a full occupation of Gaza and for Israel to reestablish settlements there, two decades after it withdrew.

The far-right Israeli finance minister, Bezalel Smotrich, told reporters on Wednesday that he hoped the government would approve the military taking control over the rest of Gaza.

“Where should we go? We have been displaced and humiliated enough,” said Aya Mohammad, a 30-year-old Palestinian who, after repeated displacement, had returned with her family to Gaza City.

“You know what displacement is? Does the world know? It means your dignity is wiped out, you become a homeless beggar, searching for food, water and medicine,” she said.

Close to 200 Palestinians have died of starvation in Gaza since the war began, nearly half of them children, according to Gaza’s health ministry.

More than 61,000 Palestinians have been killed by Israel’s assault on Gaza, according to local health officials, who said that at least 20 people had been killed in airstrikes across the territory on Thursday.

Reuters, AFP and Associated Press have contributed to this article.