Japan Airlines Co. is expected to reach an agreement with British Airways to operate joint flights and frequent flier programs, possibly as early as this month, an industry source said Tuesday.

JAL, Japan's largest international carrier, has been holding discussions with British Airways on expanding their cooperation in the cargo field to passenger operations.

If an agreement is concluded, flights operated by each airline would bear the flight numbers of both carriers, enabling each to cut operating costs without cutting service frequency. The proposed cooperation is likely to cover some of the flights between Japan and Great Britain currently offered by the two carriers, the source said.

JAL currently offers nine flights a week between Tokyo and London, seven a week between Osaka and London, and two a week between Nagoya and London. British Airways offers 14 flights a week between Tokyo and London. It suspended service from Nagoya and Osaka to London in 1998.

The proposed tieup with British Airways is a part of JAL's strategy to expand its network by forming bilateral partnerships with other airlines, instead of joining multilateral alliances.

Although international carriers have been forming multilateral alliances to cover the global market, JAL has so far been reluctant to join them. British Airways is a leading member of the global alliance "oneworld," and it is widely speculated that JAL may eventually join the consortium.

The proposed tieup with British Airways follows the announcement of JAL's flight code-sharing pact with American Airlines last year, although the two carriers have yet to reach a final agreement on the issue. American Airlines is also a member of the oneworld alliance.