John Legend and Chrissy Teigen have announced that they are expecting their first child.

The 36-year-old musician and 29-year-old model revealed the happy news simultaneously through their Instagram accounts, posting the same black and white photo of him touching her belly as she laughed.

Teigen spoke about their difficulty conceiving in her post, writing: "John and I are so happy to announce that we are pregnant. 

"As many of you know, we've been trying to have a baby for a while now. It hasn't been easy, but we kept trying because we can't wait to bring our first child into the world and grow our family."

"We're so excited that it's finally happening. Thank you for all your love and well wishes. I look forward to all the belly touching," she added.

On his page, Legend simply wrote: "We're pregnant!"

The couple married in September 2013 after six years together.