Kelsey Grammer and Kayte WalshKelsey Grammer doesn't want you to believe anything you hear about the reasons he's marrying fiancee Kayte Walsh -- unless it comes from him.

"Kayte and I are marrying because we are engaged, and we are engaged because we are in love and see no reason to postpone our happiness any longer," Grammer told PEOPLE, in response to rumors he wants a quick divorce from estranged wife Camille to hasten his upcoming marriage.

"We are planning something we wish to be a private affair among several of our friends. Anything else is conjecture and false. Kayte and I are the only reliable source for this story. End of story," the actor added.

The 55-year-old 'Frasier' star and Walsh, 29, announced their engagement in early December -- even though his divorce hasn't been finalized.