More than 11,000 people have entered the UK since the golden visa scheme was introduced in 2008

The two men in open shirts and slick business jackets were in earnest conversation at a corner table of the Savoy hotel’s American bar discussing a rather sensitive issue. Alexander Wade, the founder of Knightsbridge Wealth, was listening intently to the Hong Kong executive who was seeking his help to obtain a tier 1 investor visa — known as a golden visa — that would allow his rich Russian uncle to gain residency in Britain.

There was a catch, however: the uncle had a chequered past, with strong links to the Kremlin that might trigger alarm in the Home Office if it became known.

“I’m telling you this in confidence,” said the Hong Kong executive. “ My uncle has close ties with [Vladimir] Putin’s inner