Meghan Markle. Picture: Tolga Akmen/Pool Photo via AP

Serena Williams is "super happy" for Meghan Markle.

The tennis star has praised the former 'Suits' star as a "great girl" and couldn't be more thrilled for her pal ahead of her wedding to Prince Harry next month.

Serena said: "I'm obviously super happy for her. She's such a great girl and she is incredibly nice and I couldn't be happier for her."

Last year, the 36-year-old sportswoman married Alexis Ohanian and she is pleased to have such a "super supportive" spouse.

Speaking on the red carpet at the premiere of her documentary 'Being Serena', she told 'Entertainment Tonight': "He is super supportive and has always here for me. You know, all of my friends are, and it means a lot to me."

The couple have a seven-month-old daughter, Olympia, and Serena finds the "most rewarding" part of being a parent is when the tot smiles at her.

She said: "She doesn't have any teeth, and she's seven months, so it's like I get to see her toothless smile and it makes me so happy."

Pregnancy made the tennis champion take over a year out from competing and she has admitted it was gruelling preparing to make her return to the court earlier this year.

She said: "Sometimes, when I'm out there, it's incredibly hard. It's incredibly difficult and there's moments where I'm like, 'I don't know if this is ever gonna happen. But it does and I keep going and I keep trying to make it."

Meghan, 36, has previously spoken about her close friendship with Serena.

In her now-deleted blog, The Tig, she wrote: "She quickly became a confidante I would text when I was travelling, the friend I would rally around for her tennis matches, and the down to earth chick I was able to grab lunch with just a couple weeks ago in Toronto."