Usain Bolt expecting his first child with girlfriend Kasi Bennett

Olympian and model have been in a relationship for several years

Usain Bolt has announced that he and his partner are expecting their first child together.

On Thursday, the eight-time Olympic gold medallist announced the news with his 9.3m followers on Instagram.

Bolt shared a photo of his girlfriend Kasi Bennett cradling her baby bump while wearing a flowing red dress on a beach.

“I just want to say a KING or QUEEN is about to be HERE. @kasi.b,” the 33-year-old wrote.

Bennett, who has been in a relationship with the Jamaican former sprinter for several years, shared a series of similar photos on her own Instagram page.

In the images, the Jamaican model poses on a beach and a boat wearing the same red dress and is also pictured holding a large bouquet of multicoloured balloons.

“Our golden child. Coming soon…” Bennett captioned one of the photos.

She also described the pregnancy as the couple's “biggest blessing” and “greatest celebration”.

Fans of the couple were quick to congratulate them on their happy news, with one person writing: “I wish you and your family a great life and I hope the mother of your child has a safe delivery.”

A second person added: “Wow. So beautiful. Congrats and lots of blessings.”

While a third follower commented: “Beautiful news. Another Champ on the way.”

The couple have kept their relationship fairly private over the years and are not often photographed together.

However, the sprinting legend confirmed their romance in 2016 when he told People magazine their relationship was "serious" and shared that he would like to have three children in total.

“We just got really serious, we are taking it one step at a time. I definitely want a family, though. For me, over the years, I've waited because I want to make sure it's the right person.” Bolt said.

“I’ve always said I want three kids. The other day I hung out with my buddy who has three kids and it was crazy.

“I was like, ‘Hmmmm do I really want 3 kids?’ But yes, yes I do. I’m sure of it."

Bolt also discussed his desire to have children in an interview with the Daily Mail, saying: “Something I've learnt is it's never a good time to have kids.

“It took me a while to figure that out. It's never a good time. You just have to buckle down and do it. It's in the near future, so, hopefully. We'll see.”