Aiming to create a seamless regional bus system, the Metropolitan Transportation Authority yesterday announced that it will combine the operations of Long Island Bus with two New York City bus agencies.

The three systems, including New York City Transit Bus and Queens-based MTA Bus, will retain their separate identities but will be run as a single, streamlined operation. No service changes are planned, but officials said the move eventually should result in better coordination of routes and timetables, particularly for travel between Queens and Nassau.

The reorganization is also a major step toward a long-awaited MTA takeover of Long Island Bus from Nassau County, officials said.

Long Island Bus President Neil Yellin, who will be promoted to senior vice president for administration at the Long Island Rail Road, called the change "a step forward in terms of the evolution of transportation here on Long Island."

"People who go to work have no regard for where Nassau begins or ends, so this is a chance to give them the services that they need," he said.

Long Island Bus, one of the busiest suburban bus systems in the country, serves all of Nassau and a few parts of Queens and western Suffolk. Under a 35-year-old agreement, it is owned by Nassau County and operated by the MTA.