President Carter, backing away from his optimistic-sounding statement Monday about the American hostages in Iran, said yesterday that "there is no prospect at this time for an early resolution" of the 10-month effort to free the captives.

In taking this new tack, Carter moved to bring himself into agreement with the far more cautious line taken Monday by his secretary of state, Edmund S. Muskie, who said "it would be a mistake to raise expectations" about an early release of the hostages.

Muskie loyally said yesterday that he found the president's Monday comments "completely consistent" with his own cautious assessment. But Carter's apparent turnabout was quickly pounced on by independent presidential candidate John B. Anderson. He charged that the incident showed Carter's "talent for pointing up disarray within his own administration."

The chain of events began Monday when Carter, campaigning in Texas, said that statements being made by Iranian leaders "may well lead to a resolution" of the hostage crisis. A few hours later, Muskie, appearing at a news conference here, doggedly insisted that all U.S. efforts to establish a negotiating link with Tehran so far have proved unsuccessful.

Then came a rash of reports pointing up the apparent contradiction between president and secretary. As a result, during an informal encounter with reporters yesterday in Atlanta, Carter elaborated his views in a way that caused him to conclude: Well, I think Ed Muskie describes it accurately."

In answer to reporters' questions, Carter said, "We don't have any reason to believe that the situation has been resolved at all. . . . We don't have any prospect at this time for an early resolution of the issue."

The president noted that when he spoke Monday he had not been aware that some Iranian leaders once again had included in their list of conditions for release of the hostages a demand that the United States apologize for its past actions in Iran. That condition had been omitted in a statement Friday by Iran's principal leader, Ayatollah Ruhallah Khomeini.

Referring to the fact that the apology demand aparently has reappeared in the Iranian position, Carter added, "I'm not surprised that there was a repetition."

In a partial explanation of his optimistic statement a day earlier, the president pointed out: "There is at least a government now in Iran, and they haven't had anyone so far that could speak with authority. Now that they have in Iran a parliament and a president and an prime minister and a speaker, at least there is an entity there with whom we may be able to work out the differences."

Muskie, who talked with reporters informally at the capitol after testifying before a Senate committee, made the same point. He said, "Our conviction has been that until the government institutions are in place [in Iran] it would be hard to get a decision."

Muskie, saying that he knows Carter's attitude toward the hostage situation to be "extremely cautious," said he had read the president's Texas comments carefully and found them "completely consistent" with his own views.

Muskie insisted that Carter's statement didn't deserve the "upheat interpretation" the press and others had assigned to it. The president, he observed, had spoken of the possibility of the hostage crisis being resolved in the "future" rather than "the near future" as many people seem to have assumed.

However, Anderson, campaigning in Denver, said: "I don't think it's terribly helpful to the conduct of foreign policy to have the president speaking one way one day and another way the following day. It seems to me that, unfortunately, the president has once again illustrated his talent for pointing up disarray within his own administration on important questions of foreign policy."

Anderson also joined Republican candidate Ronald Reagon in agreeing that the United States should agree to three of the four conditions stated by Khomeini for release of the hostages: unfreezing Iranian government assets in this country, dropping all American claims against Iran and promising not to interfere in Iran affairs in the future. He said Khomeini's fourth condition -- the return of the late shah of Iran's wealth -- poses a problem because of legal and other considerations.