The Crown season 3: Helena Bonham Carter and Jason Watkins confirmed to join cast

Helena Bonham Carter is to play Princess Margaret in the third series of The Crown, Netflix confirmed today, following widely reported rumours that the Bafta-winning actress would be joining the show.

Jason Watkins has also been announced as a new addition to the cast, playing Prime Minister Harold Wilson in the hit historical drama.

They will share the screen with Olivia Colman and Tobias Menzies, previously confirmed to play the Queen and Prince Philip, taking over the roles played by Claire Foy and Matt Smith in the show's first two series.

In a statement, Bonham Carter said she was "terrified" to take over the role previously played by Vanessa Kirby. "I'm not sure which I'm more terrified about – doing justice to the real Princess Margaret or following in the shoes of Vanessa Kirby," she said. "The only thing I can guarantee is that I'll be shorter than Vanessa."

Watkins said he was "delighted" to be cast as Harold Wilson, who was Prime Minister from 1964-70 and 1970-76. "Harold Wilson is a significant and fascinating character in our history," Watkins said. 

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"So looking forward to bringing him to life, thorugh a decade that transformed us culturally and politically. And excited to be working so closely with Olivia and the whole team."

The Netflix series was recently the subject of controversy, after it emerged that Matt Smith had been paid more for his supporting role than the show's star Claire Foy. Foy was reportedly given ￡200,000 in backpay, while producer Suzanne Mackie assured reporters that there would be no such disparity in the stars' salaries when the show returns with its new cast. . “Going forward, no one gets paid more than the Queen,” she said.