The brother of an aid worker who died in an Israeli air strike in Gaza has said it is “hard to comprehend” the British Government’s inaction over the killings.

James “Jim” Henderson was one of seven aid workers who died when the World Central Kitchen (WCK) convoy was hit outside the Deir al-Balah warehouse.

The former Royal Marine, 33, from Cornwall, formed part of the relief team’s security detail and died alongside fellow British veterans John Chapman, 57, and James Kirby, 47.

On behalf of the Henderson family, James’s brother, who declined to be named, told The Times: “Accountability is the only hope of justice I have … I don’t believe our Government will hold the correct people to account, but I guarantee that our Government will sell weapons to Israel, which may in turn be used to kill our fellow citizens. It’s hard to comprehend that.”

He added: “I feel this is inexcusable behaviour, to kill my brother and his colleagues on a humanitarian mission.

“Our thoughts are with the suffering people who have been deprived of basic humanitarian needs. It’s unacceptable for our world leaders to ignore this gross miscarriage of justice.”

Meanwhile, Mr Henderson’s former rugby club paid tribute to “one of the kindest, toughest and most loyal players” to have worn the shirt.

Matthew Gray, chairman of Penryn RFC, told the PA news agency: “Penryn RFC are extremely shocked and saddened to hear the news about the death of James Henderson. There was a brief gathering at the club on Tuesday night where many of his close friends and those that had played rugby with Jimmy shared their fond memories of him.

“Clearly this tragic event, which has happened so far from Jimmy’s home town, will be felt for a long time by his family, friends and everyone in the local community who knew and loved him.

“Rest in peace, Jimmy.”

According to Penryn RFC’s Facebook page, Mr Henderson had played for the club from the youth section through to seniors.

A tribute post described him as a “force to be reckoned with” who “commanded the back row with his relentless work ethic which he instilled on to everyone that had the pleasure of playing beside him”.

The post read: “It comes with great sadness that we announce the passing of Jim Henderson. We have lost one of the kindest, toughest and most loyal players to have ever worn the Penryn shirt.

“Our thoughts and prayers are with all of Jim’s family and friends through this tough time.”

The aid convoy was hit as it was leaving the Deir al-Balah warehouse, where the team had unloaded more than 100 tonnes of food taken to Gaza on the maritime route, WCK said.

The charity immediately suspended operations in the region.

The relief team’s leader, Lalzawmi “Zomi” Frankcom, 43, an Australian national, also died in the strike, along with American-Canadian dual citizen Jacob Flickinger, 33, Polish national Damian Sobol, 35, and Palestinian Saifeddin Issam Ayad Abutaha, 25.

The attack has drawn international condemnation of what Israel called an “unintended strike”, with Prime Minister Rishi Sunak telling his Israeli counterpart, Benjamin Netanyahu, he is appalled by the killings and demanding a thorough and transparent independent investigation.

Speaking to the Sun newspaper’s Never Mind The Ballots show, Mr Sunak described the aid workers’ deaths as “an awful, awful tragedy”.

“To think that these were brave Brits who were actually risking their lives to bring aid to people in need in Gaza … To have lost their lives in these circumstances is a tragedy,” he said.

Mr Netanyahu described the attack as unintended and “tragic” and pledged an independent inquiry.

“Unfortunately, in the past day, there was a tragic event in which our forces unintentionally harmed non-combatants in the Gaza Strip,” he said in a video statement on Tuesday.

“This happens in war. We are conducting a thorough inquiry and are in contact with the governments. We will do everything to prevent a recurrence.”