John Mayer, Katy Perry are reportedly not engaged, despite left-hand ring

(UPI) -- You would think that celebrities in high-profile relationships with other celebrities would be cautious about bling on their left-hand ring finger.

But that didn't stop Katy Perry from sporting a dainty diamond ring at the MTV EMAs in Amsterdam on Sunday, prompting unavoidable rumors that John Mayer had proposed.

Though the 29-year-old singer's rep doesn't make statements about her personal life, sources told US Weekly that the couple is not engaged.

"She's not engaged," the source said. "It was just a ring that went with the outfit."

A source told E! News, however, that Perry's engagement to her 36-year-old singer-songwriter beau is "inevitable."

"Everyone wants them to get engaged," the source said of Perry's family and friends, despite Mayer's womanizing reputation. "They are so perfect together."