Niall Horan surprised fans at his Nashville concert by duetting with Noah Kahan.

The former One Direction star brought out the 'Stick Season' hitmaker to perform the Irish star's 2016 solo tune 'This Town', much to the delight of the packed crowd at the Bridgestone Arena on June 3.

The pair were backed by a pianist and violinist.

Niall said at the sold-out show: "Since we're in Nashville, there's some good songwriters around the place."

Noah, 27, later posted to X alongside footage of the performance: "Shared the stage with an icon @NiallOfficial."

Niall's tour has also seen the 30-year-old star joined by Angus and Julia Stone for a rendition of their noughties hit 'Big Jet Plane' at his solo concert at Qudos Bank Arena in Sydney, Australia, on May 1.

And the sibling duo would love to collaborate with Niall in the future.

Speaking exclusively to BANG Showbiz, they said: "Performing with Niall was so fun! He is such a legend and so is his band and crew. We had a really great night. We’ll definitely try to catch up again down the track. We’re both out on tour for the next few months but might cross paths somewhere along the way."

Asked if there are any other artists they would like to work with, Julia said: "There are so many talented artists out there. I don’t have like a list of people I want to work with, I feel like I have such a dreamy group of collaborators and hardly enough time to create everything I want to create with them."

Last year, Angus - who also releases music under the alias Dope Lemon - joined Post Malone to perform 'Big Jet Plane' in Melbourne, with the 'Circles' hitmaker, 28, like Niall, branding the tune “his favourite song for-f******-ever”.

The song was originally released by Angus, under the name Lady of the Sunshine, in 2009, before he and his sister re-recorded it a year later.