The two American reporters officially charged with slandering Soviet television yesterday formally notified the court they are withdrawing from active participation in the civil case and asked the presiding judge to dismiss the charge against them as groundless.

Craig R. Whitney of the New York Times and Harold D. Piper of the Baltimore Sun told Lev E. Almazov, president of the Moscow City Court, that to continue in active defense of their position might eventually lead to a court demand that they violate their journalistic ethics and reveal sources. Each quoted unidentified sources in dispatches that have been called slanderous by the official State Television and Radio Committee Gosterleradio.

According to Whitney and Piper, their 35-minute session with Almazov was "cordial" and he seemed affable and more open to their views than on Friday, when Piper described his manner as "very brusque." Those nuances of tone and conduct are being taken seriously here as possible sighs that the Soviets are backing away from this disagreeable and unpredictable confrontation. The two reporters said the judge did, in fact, indicate that the case could be dropped altogether.

Three alternatives are available, according to legal experts. The Soviets can dismiss the suit for want of the defendants' presence; proceed without the defendants and find for the plainings, or proceed without the defendants and dismiss the suit.

In the event of a finding for the plaintiff, the legal remedies are a court-ordered retraction and a fine of up to $432.

Soviet legal procedure, according to experts here, holds several opportunities for the Soviet government to avoid a confrontation while at the same time observing the requirments of the law and saving face, an essential ingredient in any Soviet foreign policy calculation.

All possibilities are being studied minutely for signs of how the government will proceed in what has become a major new crisis between Moscow and Washington, born of continuing Kremlin interest in silencing dissidents and cutting their connection with Western correspondents.

The disputed articles by Whitney and Piper quoted unnamed dissidents as expressing doubt about the the authenticity of a televised confession of anti-Soviet propaganda by a convicted Georgian dissident, Zviad Gamsakhurdia.

The reporters said their dispatches, carried by the Times and The Sun, which do not circulate officially here, were journalistically "fair, balanced and accurate." They added that the Soviet court in such a case does not have jurisdiction over articles published in America and distributed here.

"What this court is asked by the plaintiff to do is to rule that Soviet law may impose sanctions on reporting, though published and disseminated outside Soviet boundaries," Whitney said in a statement he submitted to Almazov. "The United States has claimed no such sweeping jurisdiction over what Soviet correspondents send from America to the Soviet Union."

Piper submitted a similar statement.

The complaint against Whitney and Piper is unprecedented in attempting to assert Soviet control over dispatches filed and published abroad. It is viewed here as having potentially serious implications for the way for foreign correspondents cover the Soviet Union. Several diplomatic sources have said the complaint, if upheld in a Soviet court, "means the return of censorship" of foreign correspondents, which was officially ended here in 1961.

The reporters said after their 35-minute closed session with Almazov that the judge voluntarily decided to further postpone the trial to July 18 from this Friday because the two had said in their previous meeting with him they had not had enough time to prepare the full, detailed responses to the complaint he had sought.

The postponement will put the trial date well after a scheduled meeting July 12 and 13 between Secretary of State Cyrus Vance and Soviet Foreign Minister Andrei A. Gromyko in Geneva.

Whitney and Piper said they told the judge they have no intention of submitting further statements or showing up at the hearing. It is known that foremost in their concerns during the week since the complaint was served on them last Wednesday has been apprehension about what would happen once they entered a Soviet court as defendents.

It is widely believed in the foreign community here that American reporters placed in such a situation would find themselves subjected to the kind of harrassment and antagonistic atmosphere and legal procedures that Soviet dissidents customarily must endure at political trials.

In their statements both reporters questioned the plaintiff's demand for a retraction.They wrote:

"(Gosteleradio) has acted with puzzling inconsistency. While it claims to desire the publication of a retraction, it makes that demand of a correspondent who cannot publish anything in the Soviet Union and who has no final authority to determine what is published" in his newspapers in the United States.

Almazov replied that he recalled a case in which a foreign journalist, whom he did not identify, had once hid a retraction printed in a Soviet sports newspaper. Such a course seems unlikely for Whitney or Piper.

In their statements, Whitney and Piper both touched on a principle that American journalists in 2 numerous court cases through the years in the United States, have argued and sometimes gone to jail to preserve: the sancity of their sources.

Whitney said: "None of the most precious prerequisites of freedom of the press in the United States has been the right to keep news resources confidential. Nothing in American law excludes Soviet correspondents in the United States from this protection. If I take further part in this lawsuit, I may be faced with a demand to reveal the sources of the news stories at issue. Doing so would endanger the principle of confidentiality and violate my professional ethics."

Both Whitney and Piper consulted with Leon Lipson, a specialist in Soviet law who teaches at Yale Law School, who was flown here Friday from London at the request of The Times. Lipson, 56, said outside the courthouse yesterday in a clipped New England accent, "It's not usual to sit on judgement on libel, slander and defamation, which takes place in another country, especially if committed by persons outside the jurisdiction of the court."

Meanwhile U.S. Ambassador Malcolm Toon met briefly yesterday with Gromyko in what is known to have been a session devoted to the suit against Whitney and Piper. The embassy would confirm only that Toon and Gromkyo met, but a spokesman refused to discuss the details.