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CHICAGO, Sept 25 (Reuters) - The planned merger of Delta Air Lines Inc (DAL.N) and Northwest Airlines Corp NWA.N to form the world's largest carrier cleared one more hurdle on Thursday, when the companies' shareholders overwhelmingly approved the deal.
Delta said 99 percent of shares voted backed the carrier's proposed acquisition of Northwest. Earlier on Thursday, Northwest said 98 percent of shares voted supported the deal.
The deal still needs regulatory approval, which is likely to come this year.
"This is another milestone toward completing a merger that brings together two unique airlines with complementary strengths that will offer unmatched global service," said Richard Anderson, chief executive of Delta, in a statement.
The new airline -- the world's largest by traffic -- would be called Delta and have its headquarters in Atlanta. Anderson would be CEO of the merged airline.
Delta and Northwest announced their merger plans in April as the price of jet fuel rallied toward a record high. The all-share deal would give Northwest shareholders 1.25 Delta shares for each Northwest share they own.
The two carriers hope the combination of their complementary operations will produce cost savings and revenues to offset the fuel burden.
"The $2 billion in annual synergies achievable through this merger are something neither carrier could have achieved as a stand-alone carrier," Northwest CEO Doug Steenland said.
"The combined carrier will have a stronger balance sheet and best-in-class liquidity, which will put the airline in a position of financial stability," Steenland said.
The airline industry is in rapid downsizing mode, with carriers cutting flights on less-profitable routes and eliminating staff.
Earlier this week, Delta and Northwest said the Federal Aviation Administration had accepted their plan for a single operating certificate.
Shares of Northwest were off 10 cents at $9.89 in afternoon New York Stock Exchange trade, while Delta shares rose 12 cents to $8.15. (Reporting by Kyle Peterson in Chicago, with additional reporting by Mark McSherry in New York and Matt Bigg in Atlanta ; editing by Gerald E. McCormick and Lisa Von Ahn)