Trade relations between the UK and Saudi Arabia stretch back more than 60 years, and one of the key elements is the British defence industry’s ready supply of weapons and military expertise to Middle Eastern nation. However, the murder of journalist Jamal Khashoggi in Saudi Arabia’s Istanbul consulate earlier this month has raised questions over the future of the multi-billion-pound arrangement.

Riyadh’s latest explanation of his death now says the critic of the regime was the victim of a “premeditated” murder by Saudi operatives.

The admission has heightened speculation that Britain’s defence companies could suddenly find themselves cut off from the billions of petro-dollars Saudi Arabia spends annually on its military.

With Whitehall’s oversight and full blessing, the British defence industry – spearheaded by BAE Systems – has forged close ties with the kingdom. The scale of the market first became clear in 1985 with the Al-Yamamah deal, when Riyadh bought 72 Tornado jets and almost as many again training and support aircraft, mainly from the company which would later become FTSE 100-listed BAE.

Labelled in the press at the time as the "biggest British sale ever of anything to anyone", it was a victory for the UK, which beat the US and France to the deal. A second sale took the value of Al-Yamamah – which means “the dove” in Arabic – to $40bn, and it became the foundation for further lucrative deals.