-By Katy Bachman

NEW YORK The U.S. Department of Justice said Wednesday that Clear Channel must divest radio stations in four markets in order to close its $19.5 billion buyout by private equity firms Bain Capital and Thomas H. Lee Partners.

Because Bain and THL own interest in Cumulus Media Partners and Univision Communications, Clear Channel is required to sell six stations in markets where it goes head to head with those radio groups, in Cincinnati, Houston, Las Vegas and San Francisco.

"Without the divestitures obtained by the Department, advertisers that rely on radio advertising in the affected cities likely would have faced higher prices," said Thomas Barnett, assistant attorney general in charge of the Department's Antitrust Division. "The divestitures will ensure that advertisers will continue to receive the benefits of competition."

The DOJ's ruling is the final hurdle in taking Clear Channel private, a deal that began more than 16 months ago. Last month, the FCC gave its OK, requiring that CC sell 42 radio stations. CC is planning to close the deal this quarter.