Alimentation Couche-Tard Inc (ATDb.TO) has won U.S. antitrust approval to buy rival CST Brands Inc (CST.N) on condition that it sell up to 71 stores in eight states, the Federal Trade Commission said on Monday.

Couche-Tard said in August that it would buy the smaller CST, which has the Corner Store markets, for some US$4.4 billion.

The company's shares rose 2.8 per cent on the approval to $63.09 in early afternoon trading on the Toronto Stock Exchange. CST edged up 0.4 per cent to US$48.54 on the New York Stock Exchange.

As of late January, Couche-Tard had 8,081 convenience stores in North America, including 6,710 which sold fuel, the company said in a news release.

The FTC required the companies to sell 70 fuel stations with convenience stores to Empire Petroleum Partners (EPLP.N) in Arizona, Colorado, Florida, Georgia, Louisiana, New Mexico, Ohio and Texas, the agency said.

Empire also has the option to buy a gas station in Albany, Georgia, the FTC said.

Alimentation Couche-Tard, which is still seeking antitrust clearance in Canada, said in a statement that it expected the deal to close on June 28.