Blake Shelton and Gwen Stefani are "extremely excited" to be engaged.

The country music star and former No Doubt frontwoman, who have been dogged by marriage rumours for years, announced the happy news via Instagram on Tuesday, with Gwen sharing a photo of herself kissing her new fiance as she showed off her engagement ring.

Taking to Twitter later in the evening, Blake responded to a message of congratulations from pastor Rick Warren, writing, "Thank you sir. We are extremely excited!"

Hollaback Girl star Gwen retweeted her beau's tweet, adding, "@RickWarren we love u!! thank u! gx."

The musical pair got engaged in Oklahoma, where they have been spending time during the pandemic with Gwen's three sons from her marriage to Gavin Rossdale.

In his own post announcing the engagement, Blake thanked his new fiancee for "saving my 2020... And the rest of my life.. I love you. I heard a YES!"

The marriage will be the second for Gwen, who was married to the Bush frontman from 2002 until they finalised their divorce in 2016. Meanwhile, it will be Blake's third trip down the aisle, after unions to Kaynette Williams and second wife Miranda Lambert.