Lady Colin Campbell has branded Meghan Markle “cheap and vulgar” in an explosive new interview.

The author, 69, who has published three books on the royals, has also urged the Duchess of Sussex to stop acting like a celebrity.

Meghan Markle has been branded “cheap, vulgar and irresponsible” by Lady Colin Campbell

Speaking to Closer magazine she said: “She was never an A-lister, so she needs to stop acting like one.

“Royalty do not behave like celebrities do. It’s cheap, vulgar and irresponsible.”

The royal writer went on to say that Meghan was “letting down” those who admire her by behaving this way.

This is not the first time that Lady Colin has warned the Duchess of Sussex of being wary of her behaviour.

The royal author says that Meghan was “never an A-lister so needs to stop acting like one”

In April she advised that Meghan should avoid becoming a “political activist” as the “royals must represent all of the people” and she should know when “keep her mouth shut”.

Lady Colin added: “There are many conservative people, all over the world, many religious people, who do not have these ‘woke’ and ‘right-on’ views.”

It comes as Meghan was revealed as guest-editor of British Vogue’s September issue.

The project saw the Duchess of Sussex select 15 women to be featured on the cover, choosing not to star herself, whom she hails “forces for change.”