The Department of Justice has cleared Delta's buyout of Northwest, saying it doesn't violate antitrust laws.

MINNEAPOLIS (AP) -- The Justice Department on Wednesday approved a much-anticipated merger between Delta and Northwest, clearing the way for creation of the world's largest airline.

After a six-month investigation, government lawyers concluded the merger would likely drive down costs for consumers without curbing competition.

The proposed merger "is likely to produce substantial and credible efficiencies that will benefit U.S. consumers and is not likely to substantially lessen competition," the Justice Department said in a statement issued by its Antitrust Division.

The merger should create cost savings by combining airport operations, information technology and other efficiencies, ultimately driving down prices for fliers, the regulators said.

The decision caps a six-month Justice Department investigation, which was closed without Justice Department objection to the deal.