Matty Healy refused to comment about his rumoured new romance with Taylor Swift, despite the pair reportedly preparing to move in together.
The 34-year-old singer took to the stage with his band The 1975 on Saturday and seemed to allude to the romance, but he stopped himself from revealing any details.
Addressing the crowd at BBC Radio 1's Big Weekend in Dundee, Scotland, Matty said: "Is it all a bit? Is it sincere? Will he ever address it?
"All of these questions and more will be ignored in the next hour. Ladies and gentleman, this is The 1975."
Matty wore a white lab coat on stage and held a bottle of red wine in his hand as he performed some of the band's hit songs.
The musician completed his look with a name badge and a pair of round glasses.
The performance comes amid reports he is set to move in with Taylor after they started dating shortly after her split from British actor Joe Alwyn.
Taylor and Joe were together for six years, but she reportedly moved on with Matty just weeks after their split.
Matty and Taylor are supposedly "so loved up" and "want to spend as much time together as they can."
The 1975 lead singer is said to have shipped over his belongings from his residence in the UK to set up with Taylor at her home in New York while he helps her to write her next album.
An insider told The US Sun : "He and Taylor are so loved up and want to spend as much time together as they can.
"Matty has already told the 1975 team that he'll be doing all the band demos in America for the foreseeable."
"He will work on his parts for their collaboration while she is on tour and has scheduled time to attend select shows to gather inspiration for her next album," they added.
The source also shared that Matty is "unphased" by Taylor's superstar status, which was reportedly one of the reasons why her relationship with Joe broke down.
Sources claimed that the pair had "differences in their personalities" and ultimately "weren't the right fit for one another."
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