ISTANBUL (AP) — A three-ship flotilla planning to reach Gaza with humanitarian aid from Turkey was prevented from sailing by Guinea-Bissau authorities, which took down their country’s flags from two ships, organizers said.

Just before the flotilla was set to sail from Turkey to Gaza on Friday with 5,000 tons of aid, a surprise inspection by the Guinea-Bissau International Ships Registry resulted in the removal of the flags from two of the Freedom Flotilla ships.

A press release by the Freedom Flotilla Coalition described the cancellation of the vessels’ registry as a “blatantly political move,” adding: “Without a flag, we cannot sail.”

The organizers blamed Israel for applying pressure to prevent the flotilla. “It is obvious, and I think it is publicly known, that there has been close contact between Israel and the president of Guinea-Bissau,” organizer and steering committee member Torstein Dahle told The Associated Press, without elaborating.