Getty ImagesThe eight-member group have previously performed at CoachellaK-pop boy band Ateez will join the likes of Lewis Capaldi, Pitbull and Maroon 5 as headliners for BST Hyde Park.
The Ice On My Teeth hitmakers will perform on Sunday 28 June - with seven other headline dates announced so far.
Ateez will be the third K-pop group to top the bill of the London festival, with Blackpink taking to the stage in 2023, followed by Stray Kids in 2024.
The eight-member South Korean band consists of Hongjoong, Seonghwa, Yunho, Yeosang, San, Mingi, Wooyoung and Jongho.
Since their debut in 2018, the group have made a name for themselves, not only in the K-pop world but breaking into the mainstream.
They boast millions of followers on social media and have completed five world tours - hitting venues in the US, Europe, Asia and Australia.
Ateez have also made history in the UK, becoming the the first-ever K-pop group to secure four consecutive top 10 albums in the UK, according to the Official Charts Company.
In addition, they were the first K-pop act to land three top 10 albums in one year.
The gongs have continued, with Ateez winning the 2025 K-pop artist of the year prize at the iHeartRadio Music Awards - beating notable names including BTS' Jimin, Blackpink's Lisa, Aespa and Enhyphen.
Getty ImagesWill Mr Worldwide achieve a world record?Fans have previously travelled from around the world to see K-pop favourites Blackpink and Stray Kids in action at London's Hyde Park, with each headliner normally attracting about 65,000 people.
Adele, Taylor Swift and Kendrick Lamar have performed at BST Hyde Park before, with pop singers Olivia Rodrigo and Sabrina Carpenter among those on the bill last year.
This year will also see a world record attempted courtesy of Pitbull on Friday 10 July - for the largest gathering of people wearing bald caps.
During the Fireball singer's sold-out tour last year, the trend went viral as thousands turned up in bald caps, sunglasses and sharp suits in tribute to Mr Worldwide.
Pitbull previously told the BBC it makes him "very happy" to look out into the crowd and see thousands of people dressed like him and singing along.
Getty ImagesOlivia Rodrigo was one of the stars of the 2025 eventThe all-male headline line-up so far also includes US country singer Garth Brooks on Friday 27 June, one day before Ateez.
US band Maroon 5 will cap off Friday 3 July, which will include special guests One Republic and Jess Glynne.
Mumford & Sons will close out Saturday 4 July, with an appearance from Holly Humberstone, and Duran Duran topping the bill on Sunday 5 July.
Lewis Capaldi will be headlining on the weekend of 11 to 12 July, with the second show added due to high demand.
Organisers say more artists are set to be announced with general tickets to see Ateez going on sale on Friday 29 May.
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