American model Gigi Hadid has confirmed that she is expecting her first child with boyfriend Zayn Malik.

The 25-year-old, who has been in a relationship with the ex-One Direction singer on and off since 2015, told talk show host Jimmy Fallon of her pregnancy after days of intense speculation.

"Obviously we wish we could have announced it on our own terms but we're very excited and happy, and grateful for everyone's well-wishes and support," she said.

"It definitely wasn't bad news and we're happy now to be excited about it."

US gossip site TMZ has claimed that the couple are expecting a baby girl with a due date of September.