The families denounced Netanyahu’s plan to expand military operations. Yehuda Cohen, the father of Nimrod Cohen, an Israeli soldier held hostage in Gaza, said from the boat that Netanyahu is prolonging the war to satisfy extremists in his government and to prevent it from collapsing.

The Israeli security cabinet is to discuss the proposal on Thursday. Critics say that extending the offensive would endanger the lives of Israeli hostages and kill more Palestinian civilians.

Israeli Prime Minister Benjamin Netanyahu was due to meet with a small group of senior ministers on Thursday to discuss plans for the military to take control of more territory in Gaza, despite mounting criticism at home and abroad over the nearly two-year-old war there.