Vinay Dube, Delta Airlines Inc. senior vice president for the Asia-Pacific region, said Thursday that Narita International Airport will remain a hub for the U.S. airline even after it launches direct flights between two U.S. cities and Tokyo's Haneda airport.

"At this point, we feel that our services to and from Tokyo Haneda are a very nice complement to our hub in Narita," Dube said at a news conference in Tokyo. "And at this point, we have no intention of changing the size and scope of our Narita operations."

On Sunday, Delta will inaugurate daily flights between Haneda and Los Angeles and Detroit, after the Tokyo airport reopened for full-fledged international services in October.

Dube also said he sees the importance of Narita airport continuing to be a hub for the foreseeable future, as it has a "very complementary role" for the airline's expansion from the United States to other parts of Asia.

Delta serves 22 destinations, including Singapore and Bangkok from Narita, which became a hub in 2008 after its merger with Northwest Airlines. Delta is the biggest foreign carrier serving Narita airport.

He said air travel demand in Asia is projected to grow fivefold to sixfold over the next 20 years backed by economic expansion, enabling airlines and alliances to avoid engaging in a zero-sum game.