A US ambassador described how the Duke of York delivered an expletive-laden attack against British anti-corruption investigators and journalists for getting in the way of lucrative trade deals, according to a secret document.
The cable is among thousands of US diplomatic documents received by whistleblowing website WikiLeaks.
Prince Andrew, who travels the globe as a special UK trade representative, led a discussion among British and Canadian business leaders in the central Asian state of Kyrgyzstan which "verged on the rude", wrote US ambassador Tatiana Gfoeller.
He treated the struggle for influence in central Asia as a rerun of the "Great Game" which pitted Britain against Russia in the 19th century, "cockily" adding: "This time we aim to win."
According to a copy of the cable published on The Guardian's website, Ms Gfoeller said that Prince Andrew won warm support from his business audience with his remarks about corruption, which included disparaging remarks about France.
During the two-hour engagement in 2008 at a hotel in Kyrgyz capital Bishkek, Andrew attacked the Serious Fraud Office probe - later closed - into alleged kickbacks related to BAE Systems' multibillion-pound Al-Yamama arms deal with Saudi Arabia, said Ms Gfoeller.
"He railed at British anti-corruption investigators, who had had the `idiocy' of almost scuttling the Al-Yamama deal with Saudi Arabia," she wrote.
"His mother's subjects seated around the table roared their approval.
"He then went on to 'these (expletive) journalists, especially from the National Guardian, who poke their noses everywhere' and (presumably) make it harder for British businessmen to do business. The crowd practically clapped."
Summarising the meeting for State Department officials in Washington, Ms Gfoeller said: "Astonishingly candid, the discussion at times verged on the rude (from the British side)."