“In relation to any discussions with Buckingham Palace there’s a long-standing convention in the United Kingdom that that’s never spoken about,” he added in response to questions on H6’s close ties to Prince Andrew.

Other politicians have also shown concern over the reach of the United Front Work Department, an arm of the Chinese Communist Party (CCP) which H6 is believed to have been associated with. The department is tasked with conducting influence operations.

Former security minister Tom Tugendhat said it showed the “the level of threat” posed by China to the UK.

“They’re trying to change the policies of the UK and other countries around the world,” he said.

“They’re trying to influence individuals not just in the royal family but in academia, in politics, in business and even sometimes in journalism.”

Talking to BBC Breakfast, Tugendhat said it was a way for the CCP to “exert influence” within the UK.

Last week, Prince Andrew said in a statement that he had “ceased all contact” with the Chinese businessman, with all meetings having been “through official channels” and “nothing of a sensitive nature ever discussed”.

H6 was invited to the prince’s birthday party in 2020 and was told he could act on his behalf when dealing with potential investors in China.

In a letter found on one of H6’s confiscated devices, the Chinese businessman was told by one of Prince Andrew’s advisors: “Under your guidance, we found a way to get the relevant people unnoticed in and out of the house in Windsor.”

It is not clear how H6 became close to Prince Andrew.

The alleged targeting by an alleged Chinese influence operation is the latest controversy for Prince Andrew, who is no longer a working royal.

It followed scrutiny of Prince Andrew’s finances this autumn, when King Charles withdrew his financial support for Prince Andrew and the costs of running Royal Lodge in Windsor, with a security bill costing several million pounds per year.