Dwayne Johnson has walked back a joke he made about new UK Prime Minister Boris Johnson being his "cousin" after a backlash on Twitter.

The Hollywood star was speaking to Good Morning Britain about his new film Fast & Furious Presents: Hobbs and Shaw when he made the light-hearted statement.

"He's family, by the way; you don't know that, but now all of Britain knows ... he's my cousin", The Rock joked.

"It's like looking in the mirror, every time I see Boris."

Johnson later followed up the comment with a since-deleted tweet in which he commended the Tory politician for saying "the people are our bosses".

He wrote: "Breaking: PM Boris Johnson is in fact my cousin (though we clearly look more like twins).

"Jokes aside, PM did say something in his speech I liked - 'the people are our bosses'.

"100% agree. The people/audience/consumer will always matter most. #ourboss"

After the tweet received some negative comments, The Rock backtracked the comment on Twitter, writing: "Well according to the people, maybe we're not related after all.

"Big mahalo to my people who I can always rely on to give me the real talk and swift perspective & education on the individual I did not know.

"Tequila on me, Britain." 

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