THE UK's Foreign Secretary demanded government officials approve her lunch with a foreign diplomat at London's most exclusive club, owned by a Tory donor.

Despite being offered alternatives with less political weight, Liz Truss insisted that she hosted US trade representative with a lunch that totalled £1400.

The boozy lunch in West London's upmarket Mayfair district was hosted at the 5 Hertford Street private members' club, owned by Robin Birley, a millionaire and half-brother of environment minister Lord Goldsmith.

Birley donated £20,000 to Boris Johnson's leadership campaign before he became Prime Minister and had also donated to the Tory party and Ukip.

He is also known to be a close friend of Conservative Party co-chairman Ben Elliot, who is also a member of the club.

The lunch occurred in June when Truss was the international trade secretary. She reportedly sought departmental funds to host a £3000 lunch at the exclusive club with Joe Biden's trade representative Katherine Tai.

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The venue has played host to top Tories including Johnson, David Cameron and Michael Gove as well as being a regular spot for Truss as she hosted "fizz with Liz" dinners with MPs and "biz for Liz" events for potential donors in preparation for a potential leadership bid.

Civil servants were concerned about the cost of the venue and its political links but Truss "refused to consider anywhere else" and considered alternatives as "inappropriate" according to official correspondences.

The proposal was referred to the department's permanent secretary, and on June 15 an official stated: "SoS [Truss, the secretary of state] is hosting Katherine Tai tomorrow for dinner. She wishes to do so in a private dining room.”

“[Her special adviser] is insisting it takes place at a private members’ club called 5 Hertford Street. She’s recommended this based on having been there before — her argument is that it’s of the appropriate size and standing.

“To my knowledge we haven’t hosted anyone there before as a department.”

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They went onto describe the venue as "obviously incredibly expensive" and a SoHo alternative - Quo Vadis - was sourced which would have cost £1000.

Truss's special adviser considered this option "inappropriate".

After Truss herself "explicitly asked" to book 5 Hertford Street, civil servants negotiated with the club to bring the price down with the events manager agreeing to waive hire fees and reduce the overall bill bringing it to £1400.

The events manager had one condition for reducing costs: that they were paid immediately after the meal which caused officials to sanction the payment via an emergency process.

An official said that the cost would have to be published as part of transparency rules but was "confident" it could be justified that the money was spent immediately to "guarantee" value for money.

The department's permanent secretary John Alty eventually said he was "content" with the situation.

A receipt shows two measures of Tanqueray dry gin, two bottles of a £153 wine and another two bottles at £130 apiece were bought for a meal where 10 people were reportedly present.

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Truss is being discussed within Tory circles as a potential leader of the party and regularly tops polls of who party members favour as Johnson's successor.

The Prime Minister has faced backbench rebellions over new Covid rules and continued allegations of sleaze after attempting to change parliamentary rules to protect Tory MP Owen Paterson from suspension along with revelations about multiple lockdown-breaking parties in 2020.

A spokesman for the Department for International Trade said: “This was a diplomatic working dinner attended by the previous international trade secretary, senior UK officials, and US counterparts from our largest single trading partner.”

Attendees at the lunch were said to be hosted in a Covid-secure and private space.