Indicted South Korean agent Tongsun Park met his American accusers face to face for the first time today, signing a formal agreement to tell all he knows about members of Congress he allegedly paid off as part of an elaborate South Korean influence buying scheme.

The actual questioning by a lie-detector backed team of Justice Department prosecutors will begin Friday, but there were indications here that the agreement - and another between the U.S. and South Korean government - prohibits asking Park about which high South Korean government officials may have been involved in the campaign of cash, gifts and entertainment designed to insure continued U.S. aid.

That restriction repartedly will not apply when Park is returned to the United States to testify in court cases. Also, should he appear before congressional committees in Washington, it is understood that there would be no barrier to questioning him on the role of high governments officials.

The scope of the questioning, it was understood, was a sensitive matter yesterday between South Korean and American officials who spent nearly 12 hours hammering out last minute details before the agreement was signed.

Presumably, the Koreans would have objected to a line of questioning that might implicate the top echelous of their government. American press reports have indicated that President Park Chung Hee was deeply involved in planning the lobbying campaign.

It is believed that the questioning here will go no higher than the two former heads of the Korean CIA named as co-conspirators in the 36 count indictment of Park.

The gist of the bargain is that Park is expected to trade his truthful testimony for Justice's dropping the charges and granting immunity from further prosecution.

The exact terms of the agreements for questioning the former Washington businessmen, who is charged with conspiring to bribe congressmen, were not released, however.

Assistant Attorney General Benjamin R. Civiletti said the papers were not made public because secrecy had been specified in the overrall agreement signed by the two governments on Dec. 31.

In Washington, Peter A. White, deputy special counsel for the parallel House investigation that has criticized the Justice Department bargain for Park's testimony, said he was "distressed to learn that the agreement is not going to be released."

[Noting the reports that Park may not be questioned about the involvement of high South Korean officials, White said, "We would need such information to show he was working for the Korean government."]

Civiletti said today that Park could be asked under terms of the agreement about anything he himself had said or done in cnnection with the alleged bribery or his use of any corporations or individuals who helped him.

The transcripts of the testimony will then be presented to a grand jury in the United States as a possible basis for future indictments. Only one members of Congress, former Rep. Richard T.Hanna (D-Cal) has been indicted so far in connection with the Korean lobbying case.

A knowledge Justice Department official in Washington cautioned against speculation that Park's testimony could lead to "a ton" of new indictments.

The official noted that prosecutors might run into statue of limitations problems on violations by some of the congressmen Park could name as recipients of illegal cash payments or campaign contributions.

[In addition, he said, the department could run into trouble corroborating Park testimony about any one-on-one deliveries of money.]

Park's testimony here will be checked periodically with lie detector tests and U.S. officials said it will be impossible for Park to "snake his eay through" the interrogation with untruthful answers.

Park told reporters after the agreements was signed that he would "do my level best to cooperate with all parties." Turning to a contingent of American journalists, he said, "Try to be good to me because I am really going through hell."

The interrogation could last for 10 days or longer. Civiletti, the senior prosecutor present, said he may leave Seoul this weekend, with his deputies continuing the questioning.