last year, is selling the New York-based telephone company's local calling business to Citizens Communications of Stamford, Connecticut, for $3.65 billion.

The deal announced yesterday would create the nation's 10th largest local-exchange carrier business with more than 3 million phone lines.

The Frontier business would account for about 1 million of those lines, with about half of them located in its primary market of Rochester, N.Y. Frontier also provides local service in 33 other markets in 13 states.

Global Crossing, a 3-year-old industry upstart based in Bermuda, paid $8.1 billion worth of stock last September to acquire Frontier, which was founded in 1899 as Rochester Telephone.

Frontier's nationwide long-distance network provided a U.S. foothold for Global Crossing, which is building a worldwide fibre-optic network to carry voice, data, video and Internet traffic. But with losses ballooning as it invests heavily in that network, Global Crossing has been evaluating potential asset sales since May.

Citizens Communications, which owns about 300,000 access lines in New York state, is an emerging player on the local phone market. It has snapped up millions of local lines from companies such as GTE Corp. to build a national network.