The first nonstop air service between Tokyo and Washington Dulles International Airport may begin as soon as this summer, according to a Japanese government plan, an embassy official said last week.

All Nippon Airways, a longtime Japanese domestic carrier, is expected to apply to the Japanese Ministry of Transportation for permission to provide the Tokyo-Dulles service, and the ministry "probably will approve" the request, said Atsuo Nozaki, the embassy's counselor for transportation.

The privately owned airline, which recently launched international service, may apply for the route as early as this week, said Thomas G. Morr, president of the Washington Dulles Task Force, a nonprofit organization that works to attract new airlines to the airport.

All Nippon would like to begin flying to Dulles in mid-July, but the starting date will depend on the approval of Japanese and U.S. regulators, said Nozaki and Morr. The flight from Dulles to Tokyo would take 14 hours, while the flight back would take 13 hours.

The new service would be a coup for the rapidly expanding airport and a boost to the competition between Japanese and U.S. carriers battling for the lucrative trans-Pacific market.

"To add nonstop Far East service to the pattern of Dulles services would be a major addition," Morr said. "We certainly are hopeful that their government would approve it."

International service out of Dulles, measured in number of passengers, grew 77 percent in 1985, Morr said. Since 1982, total passenger volume has grown 130 percent, and 10 airlines have started serving the airport, he said.

Japan and the United States agreed last April to permit six new air routes between the countries, with three to go to Japanese carriers and three to American airlines.

The Japanese Ministry of Transportation decided last week on a package of possible routes, and will now accept applications from carriers that want to serve them, Nozaki said.

All Nippon also is expected to apply for the Tokyo-to-Los Angeles route, which also is served by Japan Air Lines, the state airline. JAL is expected to apply for permission to start service between Tokyo and Atlanta. The leading trans-Pacific passenger and cargo carrier, JAL already serves five cities in the continental United States, plus Honolulu and Guam.

If the applications are approved by the Japanese government, All Nippon will have to apply to the U.S. Department of Transportation for an operating license, and JAL would have to apply to have its license amended, said a DOT spokesman, who added that such approval is likely.

DOT has been holding hearings to gather information it will use to decide which U.S. airlines will be allowed to have the other three routes. A decision is expected by late spring or early summer.

United Airlines, the largest U.S. carrier, recently acquired Pan American Airways' Pacific routes. United is considered a bigger threat to JAL because of its extensive domestic route structure, which can easily feed passengers to the Pacific routes. United already has indicated its interest in providing direct Tokyo-Dulles flights.

JAL responded to this last last week by announcing cooperation ageements with Delta Air Lines and Western Airlines.