John Mayer ended his relationship with Jennifer Aniston

John Mayer ended his relationship with Jennifer Aniston because they had "different chemistry," he told reporters Saturday after working out at an Equinox Gym in New York's SoHo neighborhood.

"People are different, people have different chemistry," said Mayer. "I ended a relationship to be alone, because I don't want to waste somebody's time if something's not right."

And before the rumors begin, Mayer said firmly: "There's no lying, there's no cheating, there's no nothing."

He also offered praise for his ex.

"Jennifer Aniston is the smartest, most sophisticated person I think I have ever met."

The "Friends" actress, 39, divorced Brad Pitt four years ago; Mayer, 30, was previously linked to Jessica Simpson.

Aniston's rep recently denied Star magazine's report that the actress is pregnant.