President Carter is "quite concerned" about the unusual Soviet action against Robert C. Toth, Moscow correspondent of the Los Angeles Times, White House press secretary Jody Powell said yesterday.

The Carter administration simultaneously raised its apprehension about the accusation against Toth to the highest diplomatic level.

Acting Secretary of State Warren Christopher, a spokesman said, telephoned Soviet Ambassador Anatoliy F. Dobrynin to express "the serious concern of the U.S. government" over the Toth case.

Christopher was underscoring a diplomatic protest note submitted in Moscow yesterday on the interrogation of Toth by Soviet security police. Soviet authorities officially declined that protest and took the initiative first by accusing Toth of collecting political and military secrets.

State Department spokesman John H. Trattner said "we see nothing in Mr. Toth's activities that could be considered to be incompatibale with his legitimate journalistic status and activities."

At the White House, Powell read portions of the U.S. protest note. It said that Soviet action in the Toth case "introduces a new and even more disturbing element into what seems to be a persistent effort by Soviet authorities to harass and intimidate American correspondents in the exercise of their profession."

Such action, the U.S. protest said, "cannot be considered in the best interest of normal U.S.-U.S.S.R. reltions" and are "inconsistent" with provisions of the 35-nation Helsinki accord of 1975 on access to information.

There was a striking example yesterday, however, of the two-track policy the Carter administration is attempting to pursue in its relations with the Soviet Union.

While diplomatic crossfire was being exchanged over the Toth case, Soviet Ambassador Dobrynin - before his telephone talk with Christopher - was celebrating over caviar and champagne with Joseph A. Califano Jr., Secretary of Health, Education and Welfare, in the HEW building at noon.

They were hailing the nenewal of two agreements in health and science, initiated in 1972, for exchange of information and scientists in public health and medical research.

Califano noted lightly but pointedly, that the caviar was provided at Soviet, not American, expense. The officials exchanged congratulatory messages over a special teletype circuit to the Soviet Ministry of Health in Moscow. The atmosphere was total cordiality.

On the more somber side of the dual Washington-Moscow track, administration sources said it is too early to judge the full consequences of the Toth controversy.

At the White House, Powell, when asked if the United States will take retaliatory action against Soviet reporters said: "We certainly do not intend to violate people's right to legitimately pursue the news just because that practice may take place in other countries." But the United States, he said, will be carefully watching Soviet handling of the case.

Administration analysts are speculating that the Soviet Union will let Toth leave Moscow after an unknown period of intermittent interrogation that will be intended as a warning both to Soviet dissdents and American reporters.

The action against Toth is simultaneously regarded as potential ammunition for mounting a counterattack in defense of the Soviet Union in the Helsinki accord review conference that opens today in Belgrade, Yugoslavia.

U.S. officials emphasize that they cannot be certain how far the Soviet Union will press the controversy, which can rebound increasingly on American relationships if it is prolonged.