Lex Greensill had penetrated the British establishment, forging close links with the country’s highest-ranking civil servants and ministers and lobbying for lucrative government contracts.

Now the Australian financier had a new sovereign client in mind, where wealth and power were more concentrated and the right relationships could transform his business: Saudi Arabia.

Before Greensill Capital collapsed this month, one of Lex Greensill’s favourite anecdotes was a camping trip he said he had taken with David Cameron and Saudi Crown Prince Mohammed bin Salman.

Accompanied by the former UK prime minister, who was now his paid adviser, Greensill visited the desert with Prince Mohammed, the kingdom’s de facto leader, according to three people who heard his account of the journey.

One of the people placed the trip during January or February 2020, shortly before the spread of coronavirus largely halted international travel. Flight records for Greensill Capital’s four private planes show a series of trips to Saudi Arabia in the first three months of last year.

A second person who heard Greensill’s account of the trip said the Australian financier explained how he bonded under the night sky with the Saudi royal, commonly known as MBS, over the fact that both men had both studied law at university.

Greensill Capital declined to comment. The Saudi embassy in London declined to comment.

The Financial Times has attempted to ask Cameron about the account of the desert camping trip several times, but the former prime minister has ignored the inquiries. His role in the company’s downfall has come under growing scrutiny, after the FT revealed he lobbied former colleagues for greater access to emergency government Covid loan schemes.

Cameron, who once stood to make tens of millions of pounds from Greensill share options before the company’s collapse rendered them worthless, visited Saudi Arabia publicly in October 2019, attending the so-called “Davos in the Desert” summit in Riyadh.

The trip — a year after the murder of journalist Jamal Khashoggi by Saudi agents — was criticised at the time by Amnesty International, which said the former prime minister's attendance would be “interpreted as showing support for the Saudi regime” despite its “appalling human rights record”.

Cameron, who charges at least £120,000 per hour for speaking engagements, frequently used Greensill’s corporate jets to travel around the world, according to several people familiar with the matter. The FT has also seen a photograph of him aboard one of these plushly furnished aeroplanes. Flight records for one of Greensill’s aircraft show numerous trips to and from Newquay airport, which is around half an hour’s drive from Cameron’s holiday home in Cornwall.

Greensill’s fleet of aircraft, an unusual luxury even for the largest multinational companies, came in useful during another visit to Saudi Arabia.

In August 2019, SoftBank chief executive Masayoshi Son and his top lieutenant Rajeev Misra had been holding meetings in the commercial centre of Jeddah when they were invited to visit Yasir al-Rumayyan in the capital Riyadh.

Rumayyan was head of the country’s Public Investment Fund, which is in turn the largest investor in SoftBank’s $100bn Vision Fund, which has backed valuable start-ups from Uber to DoorDash.

As the men looked to change flight plans, Greensill spoke up to offer them a ride on his private jet. Some of those present were amazed the unassuming Australian had his own plane. But Greensill, then 42, had recently cemented his status as a billionaire thanks to SoftBank’s investment in his eponymous finance company. He explained he had not one, but multiple aircraft.

“We need it for clients,” one attendee recalls him explaining. “We need an air force.”

Greensill’s engagement with Saudi Arabia was multi-faceted. Last June, senior Greensill executive John Luu spoke at the “UK-Saudi Virtual Fintech Week”, an event hosted by the UK’s Department of International Trade and the British embassy in Riyadh. The event’s marketing material touted the UK's “progressive regulators” and Saudi Arabia's “young and tech-savvy population".

“We are a firm that not many people have probably heard of,” Luu said at the event. “And yet, at the same time, our reach is pretty broad.”

He went on to explain that Greensill Capital was not only “part of the family” of Saudi’s PIF due to the company’s backing from SoftBank, but also that the finance firm had “just penned an agreement to become joint-venture partners” with the sovereign wealth fund.

“As part of that, we’re establishing offices in Riyadh,” he added.

PIF did not respond to a request for comment.

Luu, whose LinkedIn profile described his role as “spearheading Greensill’s expansion into Saudi Arabia”, also said at the event that his company had contracts with “some of the largest companies in the Kingdom”, but declined to name any of them.

The one company that seemed to be the target of a multiyear charm offensive in the country was state-controlled oil company Saudi Aramco.

Greensill frequently touted that his company was in line to win a lucrative contract to offer so-called supply-chain finance to Aramco, according to people familiar with the matter. Also known as reverse factoring, Greensill’s signature financing technique involves paying a company’s suppliers upfront at a discount and is known for its ability to flatter corporate balance sheets.

The finance company never actually ended up providing any supply-chain finance to the oil company, however. Aramco, which also counts Rumayyan as its chair, declined to comment.

Greensill was also involved in some even more speculative financing proposals in Saudi Arabia.

During the 2019 trip to Jeddah, SoftBank executives were examining how they could help the desert kingdom modernise the holy city of Mecca, which draws millions of visitors each year during the Islamic pilgrimage known as the hajj.

Different companies in the Vision Fund could play a role: US construction start-up Katerra to build new structures, Hong Kong artificial intelligence specialist SenseTime to offer facial recognition, while India’s Oyo could help set up hotels for visiting pilgrims.

And Greensill would package all this up into investment products to finance the project.

Son at this time believed the Australian financier was capable of funding increasingly grand schemes, according to people who know the SoftBank founder. He even frequently introduced Lex Greensill by a pithy nickname: “the money guy”.

“He was part of the overall solution for a smart city for Mecca,” said a person involved in the talks. “That's why Lex was down there. He was doing the financing.”

The grand vision, again, never came to fruition.

Additional reporting by Anjli Raval