Greta Thunberg has pushed back on criticism that a Gaza-bound flotilla she is a part of is a publicity stunt, stating that no one would imperil themselves purely for attention.

The Swedish activist is aboard one of 52 boats that form the Global Sumud Flotilla (GSF), which is travelling toward Gaza with the aim of delivering humanitarian aid to Palestinians there.

Israeli authorities have ridiculed the GSF flotilla and similar seaborne attempts to reach the territory, calling the boat Thunberg travelled on in June a selfie yacht.

Asked about these criticisms of the flotilla by the BBC's Laura Kuenssberg, the activist said: I don't think anyone would risk their life for a publicity stunt.

Speaking while sailing off the Greek coast, she asserted that the flotilla was not just a humanitarian mission but was also sending a message to the residents of Gaza that when our governments fail to step up, the people will step up.

International aid agencies have been trying to get food and medicine into the Palestinian territory, noting that Israel is restricting the flow of supplies. Israel claims it is attempting to stop those supplies from falling into the hands of Hamas, despite having approved a US-backed aid agency.

Last month, a UN-backed body confirmed that there was famine in Gaza, which the UN's humanitarian chief attributed to Israel's systematic obstruction of aid. However, Israeli Prime Minister Benjamin Netanyahu denounced this claim as an outright lie.

Thunberg stated the flotilla's objective is to break Israel's illegal and inhumane siege on Gaza by sea, as the Israeli military has long managed the waters that border Gaza.

Earlier this month, the flotilla came under attack by drones which dropped unidentified objects onto boats outside the Tunisian port of Sidi Bou Said.

Another suspected drone assault on Wednesday, off the coast of Crete, prompted Spain and Italy to deploy naval ships to assist the flotilla.

Addressing these incidents, Thunberg accused Israeli officials of making baseless threats that violate international law and questioned, Why would they attack a peaceful humanitarian mission aiming to bring humanitarian aid to a starving population?

While Israel has refrained from commenting on the drone incident, it has stated it would not allow the flotilla to reach its intended destination.

Thunberg was among 12 activists detained by Israeli authorities in June after interfering with another boat claiming to be heading for Gaza with a minimal amount of aid. She was held in Tel Aviv for one day before being deported to France.

Thunberg accused Israel of illegally kidnapping her and her fellow activists while they were in international waters, whereas Israeli officials characterized the action as preventing a breach of the maritime blockade around Gaza.