Two Turkish "superwitnesses" brought here from jails in West Germany and France last week to try to shed new light on the plot to kill Pope John Paul II in 1981 have only further confused the court trying four Turks and three Bulgarians for complicity in the attempt.

The often contradictory testimony by Yalcin Ozbey and Abdullah Catli only cast further doubts on the veracity of convicted papal assailant Mehmet Ali Agca, who is an eighth defendant in the trial.

To date, the case against the seven men on trial here for being part of the the so-called "Bulgarian connection" behind Agca's attempt on the pope's life depends almost exclusively on Agca's often changing confessions from jail and his testimony here.

Ozbey and Catli were brought here from West Germany and France -- where they are serving time on drug charges -- because they were former friends and associates of Agca in the right-wing Turkish Gray Wolves movement and were thought to have information to support some of Agca's claims.

Both witnesses were able to corroborate minor details of Agca's story, but both cast strong doubts on key parts of his testimony. One of the points challenged was Agca's allegations that one of his main coplotters and one of three other Turks with him in St. Peter's Square when the pope was shot, was Oral Celik, a Gray Wolf who is still a fugitive.

Although Ozbey had told court investigators who visited his West German jail that both Celik and another Turk, Sedat Sirri Khaddam, had told him about their involvement in the shooting, Ozbey admitted to the court yesterday that Celik and Khaddam "may have been kidding."

Catli, who admitted that he is a close friend of Celik, flatly denied Agca's allegations and Ozbey's original story by maintaining that Celik had been with him in Vienna on the day of the papal shooting.

More confusing yet was Catli's charge yesterday, and Ozbey's grudging admission, that West German police had sought to lure Celik and Catli to Germany to testify "falsely" in the case by promising up to half a million dollars and immunity from prosecution.

Catli claimed that Ozbey, at the behest of German police, had called Celik in Paris to offer both of them money and immunity if they would leave France before they could be caught there and "made to tell the truth" about the papal plot.

Catli, in a courtroom confrontation with Ozbey and Agca, said he had been standing next to Celik in the latter's Paris hideout when he received the call from Ozbey. The new charge threw the courtroom into an uproar. One West German prosecutor speculated that Ozbey's telephone call may have been an attempt to shake down Celik and Catli.

Cross-examined about the accusation by presiding Judge Severino Santiapichi, Ozbey eventually admitted that "what Catli said was true." He even gave the last names of two West German police officials who he said had put him up to the call as Kreisler and Steiner.

After a vague threat from Catli about his "future" if he persisted in alleging that Celik had been in Rome when the pope was shot, Ozbey refused to answer any further questions from the judge.

Agca, who smiled throughout Catli's confrontation with Ozbey, was pleased with at least part of the testimony. Although he called Catli's insistence that Celik had not been in St. Peter's Square "a pack of lies," Agca claimed that Catli's allegation of "German secret service" involvement was proof of his own previous allegations that various secret services -- the CIA, the Italians, the Bulgarians and the Soviet KGB -- have sought to use the case for their own ends.