Israeli military ordered to block arrival of Freedom Flotilla as ship nears Gaza

High-profile activists including Greta Thunberg on board vessel with plan to deliver humanitarian aid

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Activists on board a yacht to Gaza were on collision course with Israel's army on Sunday, as Defence Minister Israel Katz instructed troops to stop the “Freedom Flotilla” from entering the strip.

The flotilla, which plans to deliver humanitarian aid to Gaza as well as raise awareness about the dire situation there, has 12 people on board including public figures such as climate activist Greta Thunberg and French-Palestinian politician Rima Hassan.

"Turn back because you will not reach Gaza," said Mr Katz, who described the activists as "propaganda mouthpieces" for Hamas. The yacht Madleen was about 150 nautical miles from Gaza on Sunday evening.

It is expected to reach Gaza on Monday, when Ms Hassan said the crew expects to be "illegally detained" by Israeli authorities. Activists expect to have their internet cut off and belongings confiscated, making it impossible to document their possible arrest.

"During this time we will be handcuffed and under surveillance by Israeli soldiers," Ms Hassan said in a video from the deck of the Madleen. "We will most likely undergo interrogation and potentially detention, before being sent back to our countries of origin."

The possibility of an imminent clash is grabbing attention worldwide and stirring memories of previous instances over the years during which Israeli forces prevented activists from approaching Gaza by sea. In 2010, nine activists were killed after Israeli naval forces stormed the Mavi Marmara ship.

The voyage came as five more people were reported killed by gunfire near US and Israeli-backed aid centres in Gaza. At least 108 Palestinians have been killed in Israeli strikes in Gaza Strip in the past 24 hours, the territory's Health Ministry said on Sunday. It said the war's total death toll has risen to 54,880, with a further 126,227 people injured.

Mr Katz addressed his order to "turn back" to what he called "the anti-Semitic Greta and her friends", in a statement released by his office.

He said Israel “will not allow anyone to violate the naval blockade on Gaza – the purpose of which is first and foremost to prevent the transfer of weapons to Hamas, a murderous terrorist organisation that holds our hostages and commits war crimes”.

Ms Thunberg, best known as the face of a youth movement demanding action on climate change, has frequently spoken up about the war in Gaza - at times dividing her eco-minded movement. She said before the Madleen departed from Catania, Italy, that "it falls on us to be the adults in the room … we have to keep our promise to the Palestinians to do everything in our power to protest the genocide".

The yacht is carrying a small amount of humanitarian aid including baby formula and medical supplies, while also making a symbolic voyage in protest at Israel's blockade. Crew members say they are unarmed civilians who pose no threat.

Yasemin Acar, a German activist on board, said on Sunday that the crew "will certainly not listen to Israel telling us that we cannot come. She said Israel was putting Gaza under "an illegal siege, so who are they to tell us where we can go and where we cannot go?”.

Israel’s naval blockade of Gaza has been broken by activists before, with several successful instances in 2008. The most recent vessel that made the attempt, Conscience, was hit by drones in May, with activists widely blaming Israel although the military has not claimed responsibility.

On that occasion, the crew reported a breach in the ship's hull due to a drone strike shortly after midnight. There were no casualties as the crew eventually reached Malta.

The yacht Madleen is named after a Gazan fisherwoman, according to the organisation, which says the flotilla is "carrying a cargo of hope and humanitarian aid". Game of Thrones actor Liam Cunningham is also on board.

Israel blockaded all aid to Gaza for 11 weeks beginning in March. A limited amount of aid began entering last month, with food now being distributed by a private US foundation whose operations have been marred by violence.

A woman raises the Palestinian flag as the Madleen sets sail from Catania, Italy. Getty Images

Activists on board the Madleen have been posting frequent messages on social media. “When governments fail, we sail,” read one post by crew member Thiago Avila.

“This mission should not exist. It should have been done by governments, by international organisations. We only need to do this because governments are failing Palestine.”

On Saturday the crew reported reaching Egypt after a delay caused by rescuing four migrants who threw themselves overboard a vessel in distress, in a bid to escape Libya’s coastguard, according to organisers.

Sailing in the Mediterranean on Thursday, the ship was diverted by a mayday signal from an EU border patrol drone, leading it to a deflating vessel in Egypt's search and rescue zone, organisers said.