Accused spy Jerry Alfred Whitworth wrote a "resignation letter from espionage" to spy ring mastermind John Anthony Walker Jr. in 1984 but was composing a letter indicating his interest in rejoining the business at the time of Walker's arrest, Walker testified today.

In the letter, which was addressed to Walker and seized by FBI agents who questioned Whitworth hours after Walker's arrest, Whitworth referred to the "camera situation" and said, "If one or more are still wanted, I'm amenable to anything reasonable."

Walker testified that the men used photographic allusions to discuss espionage and that Whitworth's language was a "clear indication to me" that Whitworth "wanted to get back into espionage."

That testimony was permitted over the objection of defense lawyer James Larson, who termed it the "sheerest speculation I can imagine."

In his third day of testimony against the man he described as his best friend, Walker said Whitworth was extremely curious about the "buyers" of the information, but that Walker never told him it was the Soviets.

He said he concealed the buyers' identity at first, so as "not to scare him away" and that later "there was no reason to tell him who the buyer was as long as the material was flowing."

In order to prove their espionage case against Whitworth, prosecutors must show that he knew the material could be used to the injury of the United States or the advantage of a foreign country.

Prosecutors have said they will show that Whitworth eventually became aware the material was going to the Soviets.

In his testimony today, Walker detailed the fraying relationship between Whitworth and the Soviets, Whitworth's complaints about inadequate pay and his frequently expressed fears that the ring would be exposed.

"He was overly concerned that some accident or mistake would occur," Walker said. He said that Whitworth, on several occasions when he saw press reports that a Soviet spy had been arrested, asked Walker to check with his "buyers" to find out what had gone wrong.

"I constantly reassured him that we would not make the mistake these people had made . . . ," Walker said. "I couldn't see the FBI as any threat at all really, unless something catastrophic happened like a tree fell on my car while I was going to a drop site."

"I guess May 19 was a pretty big surprise, huh?" said Assistant U.S. Attorney William S. Farmer, referring to the day last year when FBI agents followed Walker as he left a package of classified documents for his Soviet contact in rural Montgomery County.

"Yes, sir, but that took a snitch," Walker replied bitterly.

Walker's daughter and his ex-wife tipped off the FBI to the operations of the spy ring in November 1984.

The trial was disrupted today by a heated exchange between the U.S. attorney and defense lawyers over the propriety of a defense attorney's out-of-court statements.

The confrontation, which took place outside the hearing of the jury, continued in the hallway outside the courtroom when Whitworth's wife, Brenda Reis, called U.S. Attorney Joseph P. Russoniello a "hypocritical bastard" who had been trying the case in the press.

Russoniello, who is not prosecuting the case personally, made an unexpected appearance in the courtroom just before the lunch recess to complain to U.S. District Judge John P. Vukasin Jr. about statements by defense lawyer Tony Tamburello.

In remarks to reporters before Walker started testifying Monday, Tamburello termed the government's plan to use him as its star witness "a perversion of justice." Russoniello said that unless defense lawyers agreed to refrain from such statements, "I feel some obligation as U.S. attorney to respond."

Tamburello contended he had acted in an "upstanding manner." He added, "I really think Mr. Russoniello's grandstanding appearance here without even telling us is inappropriate." Vukasin admonished lawyers for both sides to adhere closely to a court rule barring attorneys from commenting on the witnesses or evidence in a trial.