Katy Perry's publicists refuse to comment on engagement reports

Katy Perry's publicists are refusing to confirm or deny reports suggesting the singer is engaged to wed boyfriend John Mayer.

The I Kissed a Girl hitmaker was spotted with a ruby ring on her wedding finger during a night out with John Mayer on Valentine's Day (14Feb13), suggesting he had proposed.

However, Katy Perry's handlers are refusing to discuss the speculation, offering up a firm "no comment" instead.

The 28-year-old pop star, who split from her first husband Russell Brand at the end of 2011, was photographed wearing her new ring as she left Vicenti restaurant in Brentwood, California with her boyfriend.