Prince Andrew allegedly had 40 prostitutes brought to his five-star hotel over the course of four days during an official visit to Thailand, a royal historian has claimed.

According to author and historian Andrew Lownie, the disgraced Duke of York — then serving as the UK’s Special Representative for International Trade and Investment — arranged for the women to visit his room during a taxpayer-funded trip to mark the Thai king’s birthday celebrations.

Lownie told the Daily Mail that the encounters were facilitated by “diplomats and others” while Andrew was representing Britain overseas.

Between 2001 and 2011, the Duke acted as the UK’s trade envoy, though Lownie claimed that the now-King Charles, then Prince of Wales, had privately warned Prime Minister Tony Blair against giving his brother the role, fearing Andrew would “chase women and play golf” rather than focus on diplomacy.

Lownie, who detailed Andrew’s controversial career in his book Entitled: The Rise and Fall of the House of York, said the Duke often refused to stay in British embassies during official trips, instead insisting on luxury accommodation and adding up to two weeks of “private time” to his itineraries.

Former trade envoy Paul Scully, who served as a Conservative MP, told Times Radio that during one visit to Bangkok — for the Thai king’s funeral — Andrew “booked out pretty much an entire floor” at the Mandarin Oriental Hotel, at an estimated cost of £50,000.

The new allegations surface as Buckingham Palace reportedly begins formal proceedings to strip Andrew of remaining official titles and evict him from Royal Lodge, his Windsor residence.

Lownie further claimed that Andrew also used his trade envoy position to advance his personal business interests. On one occasion, he reportedly helped his business associate David Rowlands secure a meeting in China and obtain a banking licence in the Middle East.

Despite growing scrutiny, Lownie said there remains a “conspiracy of silence” surrounding Andrew’s decade-long tenure as Trade Envoy, as government files from that period have yet to be released.

Speaking to Sarah Vine before the palace’s latest move against the Duke, Lownie argued that Andrew’s behaviour had brought “disrepute” on the monarchy and that he should have been “thrown under the bus” long ago.

“If there had been proper scrutiny of Andrew during his time as Trade Envoy, some of these problems might not have happened,” he said.