Helena Bonham Carter says The Crown should stress to viewers it's a drama

Helena Bonham Carter has said The Crown has a “moral responsibility” to tell viewers that it is a drama, rather than historical fact, in the wake of calls for a “health warning” for people watching the series.

The actor, who played Princess Margaret in series three and four of the Netflix hit drama, told an official podcast for the show that there was an important distinction between “our version”, and the “real version”.

In the podcast episode, which was released on Monday, Bonham Carter said: “It is dramatised. I do feel very strongly, because I think we have a moral responsibility to say, ‘Hang on guys, this is not … it’s not a drama-doc, we’re making a drama.’ So they are two different entities.”

She called the research by the show’s creator, Peter Morgan, “amazing”, adding: “That is the proper documentary. That is amazing and then Peter switches things up and juggles.”

Related: The Crown's fake history is as corrosive as fake news | Simon Jenkins

Her views came after criticisms of the show’s historical accuracy prompted the culture secretary, Oliver Dowden, to say he planned to write to the streaming network to request that a disclaimer was put up before the show was played, so viewers would not misinterpret the portrayal as historical truth.

Dowden told the Mail on Sunday: “It’s a beautifully produced work of fiction, so as with other TV productions, Netflix should be very clear at the beginning it is just that … Without this, I fear a generation of viewers who did not live through these events may mistake fiction for fact.”

Accusations of inaccuracies in Peter Morgan’s production span from repeatedly showing the Queen “wrongly dressed for trooping the colour” to disputes over Prince Charles’s fishing technique.

But the biggest bones of contention have been about the depiction of Charles’s marriage to Diana. He is portrayed phoning Camilla Parker Bowles every day in the early years of the marriage, and Diana is depicted as forcing plans for the couple’s trip to Australia to be changed after throwing a tantrum.

Currently viewers are warned that the show contains nudity, sex, violence and suicide references, and is suitable for viewers aged 15 and above.

Netflix has been contacted for comment.