'The Crown' bosses have been branded "cruel" for showing Prince Philip pursing an affair in the new series.

The fifth season of the Netflix drama is set to hit screens next month and one plot will see the late Duke of Edinburgh - who died in April 2021 - grow close to old friend Penny Knatchbull, who is now Countess Mountatten of Burma, and confiding in her about his marital "problems" while teaching her carriage driving.

Royal experts have slammed the decision to include the "cruel rubbish" so soon after Queen Elizabeth died in September.

The late monarch's former press secretary, Dickie Arbiter, told The Sun newspaper: “Coming just weeks after the nation laid Her Majesty to rest next to Prince Philip, this is very distasteful and, quite frankly, cruel rubbish.

“The truth is that Penny was a long-time friend of the whole family. Netflix are not interested in people’s feelings.”

Majesty magazine editor Ingrid Seward insisted the plot is in "exceedingly bad taste" and dismissed suggestion there is any truth to the storyline.

She said: “It’s in exceedingly bad taste.

“This is fiction. There’s no way in a million years he’d discuss his marriage with anybody. The royals probably won’t watch it for their own sanity.”

The fifth season of the show will see Philip played by Jonathan Pryce opposite Imelda Staunton as the queen and Natascha McElhone as Penny, who was more than 30 years younger than the duke.

In 2018, show creator Peter Morgan admitted some parts of the show require "leaps of the imagination" from the writers, even though it is thoroughly researched.

He said: "We have to make some sort of leaps of the imagination, about how people were feeling.

"Maybe sometimes I get it wrong, because they aren't friends of mine. So it's a tricky one."

And Peter admitted he feels a "responsibility" to portray real events with a level of accuracy but warned fans they shouldn't take the whole programme as being completely true to history.

He said: "I feel the responsibility of that, and whether I'm misjudging it, or whether I've oversimplified it, or whether my version – which I'm happy to say is just me having a punt, I'm just guessing – gets taken too seriously, [because] I don't want to be part of creating bogus history."