Isla Fisher has revealed she repeatedly called Niall Horan the wrong name backstage on a TV show and admits she thought the rapturous applause from the studio audience was for her and not him.

The 42-year-old actress was chatting to James Corden on The Late Late Show about her last time on the show, when she played Spill Your Guts with Ewan McGregor and Niall Horan — and the Now You See me star admitted she had no idea who the Mullingar man was.

"I kept calling him Neil backstage," she revealed. 

"Then when (actor) Ewan McGregor and I came through the curtain [on the show], just as we did now, everyone was really screaming at us and we had a moment.

"It wasn't for us, it wasn't for us at all... It was for Niall," Fisher added.

Corden then chimed-in, saying, "He does court the screams," before Fisher said, "He'll always be Neil to me."

Horan recently took to social media to express his delight at reaching an impressive one billion streams on Spotify.

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