Radio DJ Scott Mills has admitted that he made Katy Perry cry live on air after bringing out a Russell Brand lookalike.

Speaking to The Sun, Radio 1 star Mills said that he was interviewing the pop songstress via video when the incident happened.

He surprised Perry - who was married to Russell Brand at the time - with an impersonator of her then-husband, causing her to run out of the room crying. He said:

"Something was up - I couldn't put my finger on it but she seemed on edge. Anyway, we thought it would be funny to get a Russell Brand lookalike to surprise her."

Mills continued: "Well, she ran out of the room screaming. My producer told me she was in tears in the next room, while I tried to smooth it over with viewers. I have no idea why it freaked her. For all I know they were having marriage problems. But she eventually did come back on screen. When there was a break she whispered in my ear, 'You better play my songs forever!'. Looking back, we were pushing our luck."

Katy Perry and Russell Brand divorced earlier this year after marrying in 2010.