Struggling Japan Airlines Corp.'s potential partnership with Delta Air Lines Inc. will not automatically open new vistas for the Japanese air carrier, according to former U.S. Transportation Secretary Norman Mineta.

He made the comments in a recent interview with Kyodo News as Delta tries to woo JAL into its alliance and American Airlines Inc. seeks to keep it from defecting ahead of a Japan-U.S. "open skies" agreement taking effect next year.

"Open Skies does not mean that antitrust immunity is automatic . . . There is a whole bunch of criteria that you have to meet," said Mineta in his office in Washington.

Mineta, an adviser to American Airlines, was referring to the question of whether U.S. authorities will waive antitrust rules and provide unlimited opportunities for joint marketing arrangements, including determining prices and selling tickets together.