By James Silver
Radio 4's The Report
The vast ballroom at the Dorchester - one of Europe's most exclusive hotels - was filled with London's oil aristocracy, sipping fruit juice from the dry bar.
Trade is burgeoning in both directions between Britain and Libya
It was a lavish affair. A mountain of fruit covered a huge table, while the queue for the buffet - an Arabic feast - snaked across the room.
We were there at the invitation of the Libyan People's Bureau to celebrate the 40th anniversary of Colonel Gaddafi's military coup.
The occasion also symbolised the thriving trade relationship between Britain and the former pariah state, which renounced its pursuit of weapons of mass destruction (WMD) in 2003 and accepted "the hand of friendship" from then Prime Minister Tony Blair, in a summit hosted by the Libyan leader in a tent in the desert just outside Tripoli a year later.
Our hosts were certainly welcoming enough, but there was more than a whisper of paranoia in the air too.
A lone photographer was eyed suspiciously. Wherever we went people edged away from our microphone.
Libya's torrid spell in the headlines, in the wake of the release of the Lockerbie bomber Abdelbaset Ali al-Megrahi meant that few of the guests - and none of the Libyans - wanted to risk being seen talking to the media.
"I'm not talking to you," one British business leader based in Tripoli said, turning his back on us. Another Briton in a pinstripe suit could not scurry away from us quickly enough.
Finally, a Manchester-based architect, David Cash took pity on us, telling us how he had gone to Libya to pitch for work and was eventually commissioned to design a number of universities.
"We went out [to Libya] and we were interviewed on a Monday and by the end of the week we had been to four different sites in the country," he explained.
"Three months later we had been commissioned to design seven universities which seemed an exciting proposition.
"You don't often get the opportunity to design seven universities in one go," he added of the deal worth "millions".
But if British companies are flooding into Libya - and there are at least 150 with outposts there now, including BP, HSBC, M&S and Rentokil - the traffic flows northwards too.
With a huge cash surplus estimated to be around $100bn (£59bn) from energy revenues, Libya has set up the Libyan Investment Authority (LIA) to safeguard the country's future by making acquisitions around the world. The LIA is expected to open a London base soon.
Further evidence of the country's flourishing presence in London can be found just a stone's throw from the Dorchester.
Portman House, a sleek commercial premises on Oxford Street, was sold to the Libyans for £155m ($258m) in July.
The Libyans bought Portman House for £155m
In December the LIA also acquired a prestigious office building opposite the Bank of England for £120m ($200m).
"When [the LIA] came to see us last year, they said: 'We are ready to spend money'," said Jeremy Grey, managing director of property agency James Andrews, who advised the Libyans on the purchase of Portman House.
He told us that he is currently looking for other potential acquisitions to add to the LIA's portfolio of investments.
"They are cash-rich and very sensible investors," he said. "And they haven't been affected by the credit crunch."
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