Spanish media reported that the organisers would meet to decide whether to resume the expedition later on Monday.
Among the activists from dozens of countries were Thunberg, actors Liam Cunningham of Ireland and Eduard Fernandez of Spain, as well as European lawmakers and public figures, including former Barcelona mayor Ada Colau.
The flotilla is expected to arrive in Gaza in mid-September and comes after Israel blocked two activist attempts to deliver aid to the devastated Palestinian territory by ship in June and July.
The United Nations has declared a famine in Gaza, warning that 500,000 people face “catastrophic” conditions.
The war was triggered by an unprecedented cross-border attack on Israel by Palestinian militant group Hamas on Oct 7, 2023, which resulted in the death of 1,219 people, mainly civilians, according to an AFP tally based on official data.
Palestinian militants also seized 251 hostages, with 47 still held in Gaza, including 25 the Israeli army says are dead.
Israel’s retaliatory offensive has killed at least 63,459 Palestinians, mostly civilians, according to figures from Gaza’s Hamas-run health ministry which the UN considers reliable.
