An Irish ship has dropped out the international flotilla preparing to break an Israeli naval blockade of the Gaza Strip as pro-Palestinian organizers accused Israel of sabotage and declared the convoy may sail from Greece without permission.

Activists said Thursday they discovered damage to the engine of the Irish boat Saoirse in the Turkish port of Gocek, where it has berthed for the past few weeks.

They called the damage an act of sabotage committed by professional divers and blamed it on Israel, which has warned it will not allow the flotilla to breach the Gaza blockade. An Israeli foreign ministry official ridiculed the allegations, telling a Swedish news agency that they sound like a plot from a James Bond movie.

Organizers said the Irish boat could have sunk with 20 activists on board if it had gone to sea with a damaged engine. On Monday, they reported similar damage to the Swedish ship Juliano at the Greek port of Piraeus and also blamed it on Israeli sabotage.

The French news agency, quoting coordinator Claude Leostic, said the flotilla will depart for Gaza “all together, no matter what” when the Juliano is fixed, likely by Saturday. An American activist on board a U.S. vessel said Greek authorities were bowing to Israeli pressure and deliberately stalling their departure.

Israeli Prime Minister Benjamin Netanyahu said Thursday that his country is fully entitled to stop what he called “efforts to smuggle” weapons into Hamas-controlled Gaza – which he called the militant Palestinian group's “terror enclave.”

Earlier, Israeli Defense Minister Ehud Barak said if the ships insist on challenging the Gaza blockade, they will be intercepted by the Israeli Navy and the organizers will be responsible for any injuries or damage.

Israeli officials say they hope to avoid a repeat of its botched raid on a Gaza-bound flotilla last year, when nine pro-Palestinian activists were killed in a confrontation with Israeli commandos who boarded a Turkish ship.

Organizers say they hope to sail to Gaza with several boats and two cargo ships loaded with humanitarian aid for the Palestinians. Most of the vessels are docked in Greece.

About 300 people plan to join the convoy, including journalists, politicians, writers and religious figures.

Israel, the United States and the United Nations have urged the flotilla to sail to Israeli or Egyptian ports and transfer its cargo legally to Gaza over land.