Sealed with a kiss — pop stars Niall Horan and Hailee Steinfeld seemed to have confirmed long-standing rumors that they're a couple.

According to The Sun, Radio 1 producer Fiona Hanlon revealed during an interview with Nick Grimshaw that she had seen Horan and Steinfeld kissing at BBC's Biggest Weekend in Swansea days ago.

"They were snogging, they were!" she said. "So cute."

Horan and Steinfeld have been fueling romance rumors for months. In March, Steinfeld uploaded a photo to Instagram that found her donning a Horan T-shirt. And the shot's caption featured coordinates that ultimately pointed to the O2 Academy in Brixton, London, where Horan had performed on Thursday, March 22.

Steinfeld told Us Weekly earlier this year that she doesn't like sharing the intimate details of her life...but she didn't deny the relationship, either.

“I feel so lucky that [my fans] care enough about me to know what I’m doing every second of every day, but I think that sometimes it’s hard for people to realize that there are boundaries to a person’s life and personal life,” she said. “I am a very private person. I do love that I have the opportunity to share with them what I’m comfortable with and they’re there to listen and support me.”

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