A former senior Foreign Ministry official will be called to testify Dec. 1 on an alleged secret pact between Japan and the U.S. over the cost of Okinawa's reversion to Japan in 1972, the Tokyo District Court said Tuesday.

Masaaki Gabe, a professor at the University of the Ryukyus, and others are suing for the release of documents they believe prove the pact's existence. The government has repeatedly denied the existence of the secret deal, but Bunroku Yoshino, then the ministry's American Bureau chief, suggested the opposite in a statement submitted to the court and in interviews with the media.

The focus is now on whether Yoshino, 91, will admit to the agreement in court, dealing a blow to the government, which has argued it does not possess any documents relevant to the case and is seeking to have the suit thrown out.

The Foreign Ministry has approved Yoshino's appearance in court.

At issue are three documents that were declassified by the U.S. government earlier this decade, including one indicating that Japan secretly agreed to cover $4 million in costs that Washington was supposed to pay to restore farmland in Okinawa that had been used by U.S. forces.

Gabe, who has studied the declassified documents, will also testify Dec. 1.