NEW YORK - A Tiffany & Co. subsidiary is suing Costco, claiming the wholesale club operator has been selling engagement rings wrongly labeled "Tiffany" rings.

The high-end jeweler filed suit in U.S. District Court in New York on Thursday.

Tiffany alleges trademark infringement, counterfeiting, unfair competition, injury to business reputation, false advertising and deceptive business practices. The company says the rings are not in fact Tiffany rings, nor are they in any way properly associated with Tiffany.

A representative for Costco Wholesale Corp. in Issaquah, Wash., could not be reached immediately for comment.