As the world's two largest carriers vie to form a strategic tieup with crippled Japan Airlines Corp., opinions are split over whether a JAL alliance with Delta Air Lines, the biggest, would create unfair competition and sting consumers.

JAL's state-run turnaround body reportedly prefers a tieup with Delta.

Industry observers have warned that a Delta-JAL tieup would be too dominant in the trans-Pacific travel market and that the U.S. government is unlikely to grant the alliance antitrust immunity status. Immunity will be crucial if JAL, which is expected to file for bankruptcy next week, is to take full advantage of the partnership and bolster the SkyTeam alliance.