Prince Harry and Meghan Markle have been accused of using their royal titles to further their political beliefs in a breach of protocol. The Duke and Duchess of Sussex hit the headlines this week when they launched an attack on Meta for scrapping its fact-checking programme.
Ironically, they were speaking just two weeks after Meghan, 43, re-launched her Instagram in a bid to plug her new Netflix show and lifestyle brand.
Mr Gardiner, who is also director of the Margaret Thatcher Center for Freedom, is an ally of Donald Trump and fierce critic of the Sussexes.
He has been the driving force behind attempts to force the publication of Prince Harry's, 40, immigration record after he admitted to drug abuse in his memoir Spare.
He told the Daily Beast that Harry and Meghan had made a "clear intervention on a deeply political matter, specifically the contentious issue of censorship on social media in the United States," adding it was a "hot-button political topic, particularly in the current climate".
He dismissed suggestions they are able to enter the political field as they are no longer working royals by pointing out they still use their Duke and Duchess of Sussex titles.
Mr Gardiner went on: "For members of the royal family to engage in such overtly political matters is, quite frankly, highly inappropriate.
It goes against royal protocol. Their use of these titles to further their personal and political agendas makes a mockery of the royal family’s customary neutrality. Their statement wasn’t a moderate call for dialogue or understanding; it was an outright political rant."
Harry and Meghan reacted this week to the news that Meta was disbanding its fact-checking service. Chief Executive Mark Zuckerberg admitted the team had become "too politically biased" and the company wanted to "get back to our roots and focus on reducing mistakes, simplifying our policies and restoring free expression on our platforms".
"Contrary to the company’s talking points, allowing more abuse and normalising hate speech serves to silence speech and expression, not foster it."
They labelled Meta "deeply deceptive" over its rollback of protections despite commitments to parents and families calling for change, accusing it of contributing to a global mental health crisis.
