Dwayne Johnson has tended to shy away from politics. But today he has announced he is officially endorsing Joe Biden and Kamala Harris for the presidential office of the USA.

Johnson made the announcement in a seven-minute long video that he posted on Instagram.

"As a registered Independent for years now with centrist ideologies, I do feel that Vice President Biden and Sen. Harris are the best choice to lead our country, and I am endorsing them to become president and vice president of our United States," Johnson announced.

He first explains his reasons for his support of the Democrat nominees.

The wrestler-turned-actor also shares a conversation he had with the former Vice President and Senator.

Dwayne Johnson praised Biden's "incredible career", praising his "great compassion and heart and drive, but also soul."

He described Kamala as "smart, tough" and "a certified badass."

Biden and Kamala answered Johnson's question about how they were going to earn the respect of the American people, emphasising "taking responsibility" and being "honest."

Dwayne Johnson concludes the video reiterating what the Presidential hopefuls stand for: "There’s a lot of ways that we as a human race can make progress. But the most powerful way for us to make progress, to me, is through humanity, is through decency.

"Progress through humanity, progress through decency, through equality. Progress through kindness, because kindness matters."

Watch it in full here.