Climate activist Greta Thunberg in a video message warned on Friday that Israel could mount a major attack within 48 hours on the Global Sumud Flotilla, an international convoy of ships bound for Gaza carrying food, medical supplies and other emergency aid.

Thunberg said in the clip: “An attack will not stop our mission. We will stand with the oppressed.”

Her warning came as organisers and participating countries stepped up security measures for the convoy.

According to organisers, naval vessels from Italy and Spain have been deployed to accompany and protect the flotilla, providing both national and international oversight to reduce the risk of clashes or interdiction at sea. The escorts are intended to ensure the safe passage of aid ships amid high tensions in the region.

The flotilla, made up of vessels from several countries, aims to deliver basic necessities to civilians in the Gaza Strip and draw global attention to the humanitarian crisis there.

Flotilla leaders and participating activists have pledged to continue the mission, citing international law, human rights and emergency relief obligations.

Organisers acknowledge the mission carries significant risks. Israel has in the past intercepted and taken action against similar aid convoys, citing national security concerns — a history that has made any maritime humanitarian effort to Gaza sensitive and potentially volatile.

As of now, Israeli authorities have not publicly confirmed or denied Thunberg’s specific warning.

Supporters say the flotilla’s objective is purely humanitarian: to deliver lifesaving supplies and spotlight the civilian suffering in Gaza.

Critics and security experts, however, warn that any naval confrontation could escalate rapidly, endangering crew and passengers and further complicating regional tensions.

Despite the threats, flotilla organisers say they will press on.

“We will not abandon the people of Gaza,” one coordinator told reporters. International monitors aboard some vessels will document events, organisers said, to ensure transparency and accountability.