Niall Horan was overwhelmed by the atmosphere and the fans' response to the One Love Manchester concert.

The One Direction star, 23, was one of a number of stars who performed on Sunday (014Jun17) at the event organized by Ariana Grande to benefit the injured and the families of the 22 fans that were killed in a suicide bombing at the end of her gig at England's Manchester Arena last month (May17).

Niall was nervous about taking the stage at the Emirates Old Trafford cricket ground as he thought the concert might be a downbeat occasion, but was delighted by how music pulled people together in the wake of the tragedy.

"Music is one of those things that pulls people together and everyone enjoys music of some sort, it was great," he tells U.K. breakfast TV show Lorraine. "Music wins again."

He explains, "I was kind of nervous about it, didn't know how to play it out and how it was going to play out. Was it going to be real somber or good fun? It turned out it was an unbelievable mix of everything."

The star took particular delight in one of the iconic moments of the gig broadcast to viewers in 50 countries, when a British policeman was shown dancing with children in the crowd.

"Things that I'd seen over the course of the day, the policeman dancing with kids in the crowd, making these big circles and dancing with them, it was just an all-round unbelievable day and I'm very happy that it happened and I'm happy that I was there," he says.

The This Town singer was honored to be part of a bill that included many of pop's biggest stars, including Miley Cyrus, Justin Bieber, Katy Perry and Pharrell Williams.

"To get that call and to be invited was a real honor," he explains. "Just to be there on the day it was just unbelievable."

The concert raised more than $3 million for the We Love Manchester victims' fund, which was set up to help the families of the 22 who died as well as those injured in the attack.

More money is likely to be added to the total, as Ariana, 23, has released the two songs with which she closed the gig, her 2015 hit One Last Time, and the classic tune from The Wizard of Oz film, Somewhere Over the Rainbow, as charity singles.