H6 How Yang Tengbo became the man Andrew was 'desperate' to keep close by

How did a junior Chinese civil servant who arrived in Britain to do a master's degree at York University end up as such a close confidant of the Duke of York that he was described as the "very top of the tree" by the prince's adviser?

- Jessica Elgot

Yang Tengbo, 50, also known as Christopher Yang, was able to move in the highest circles of the British establishment. He was invited to Prince Andrew's 60th birthday party at Royal Lodge in Windsor, joined visits to St James's Palace and Windsor Castle, attended a lunar new year celebration at Downing Street with David Cameron and was pictured in black tie alongside Theresa May and her husband, Philip.

Yang was the chair of Hampton Group, a strategic advisory group that said it could advise UK companies on their affairs in China, with offices behind the Ritz hotel in Mayfair, London.

He was also a senior member of the committee of Pitch@Palace in China, the duke's Dragons' Den-style initiative, which offered opportunities for entrepreneurs to meet investors.

Yang was filmed for a Chinese television documentary in which he showed photographs of himself alongside the former prime ministers Cameron and May, displayed prominently on his desk. He appears to have held senior positions in UK-China business groups, was described as the executive chair of the China Business Council in the UK, and was an honorary member of a Sino-British business association, the 48 Group Club, which had a number of prominent UK figures as members.

According to court documents, Yang was so close to the Duke of York that he was authorized to act on his behalf in an international financial initiative with potential partners and investors in China.

Investigators uncovered fawning letters from one of Prince Andrew's advisers and a briefing note connected to the Chinese embassy, which described the duke as "desperate".

In the judgment, rejecting his appeal against the decision to exclude him, the judge found he had "won a significant degree, one could say an unusual degree, of trust from a senior member of the royal family who was prepared to enter into business activities with him.