Federal regulators have cleared Sprint Corp.’s proposed acquisition of affiliate U.S. Unwired Inc.

The Federal Trade Commission said it had agreed to “early termination” of its review of the $1.3 billion deal without requiring any changes.

Sprint said July 11 that it planned to buy all outstanding shares of Lake Charles, La.-based U.S. Unwired for $6.25 each. Sprint also would assume $266 million of U.S. Unwired’s debt.

U.S. Unwired sells Sprint-branded services in nine southern states and serves 500,000 subscribers. It has 600 employees and reported 2004 revenues of $408 million.

The purchase would end a legal history between the parent and affiliate companies, specifically stopping U.S. Unwired’s request for a court injunction to stop Sprint’s pending acquisition of Nextel Communications Inc.