Israeli forces have stopped 13 boats carrying foreign activists and aid bound for Gaza, but 30 boats are continuing to sail towards the war-ravaged Palestinian enclave, flotilla organisers said on Thursday.

Axar.az a video from the Israeli foreign ministry verified by Reuters showed the most prominent of the flotilla's passengers, Swedish climate campaigner Greta Thunberg, sitting on a deck surrounded by soldiers.

"Several vessels of the Hamas-Sumud flotilla have been safely stopped and their passengers are being transferred to an Israeli port," the Israeli foreign ministry said on X. "Greta and her friends are safe and healthy."

The Global Sumud Flotilla, transporting medicine and food to Gaza, consists of more than 40 civilian boats with about 500 parliamentarians, lawyers and activists.

The flotilla put out several videos on Telegram with messages from individuals aboard the various boats, some holding their passports and claiming they were abducted and taken to Israel against their will, and reiterating that their mission was a non-violent humanitarian cause.