President Reagan ruled out again Tuesday negotiations with the captors of nine American hostages and said liberating them from their Lebanese captors remains a "great problem" despite the release of an Indian prisoner.

The White House, meanwhile, tempered expressions of pleasure at the release of the Indian in Beirut with "the knowledge that nine innocent Americans are among those still held hostage in Lebanon."Mithileshwar Singh, a Beirut University professor who is a legal resident of the United States, was turned over to the U.S. ambassador to Syria in Damascus Tuesday after being freed in Lebanon on Monday.

Singh, who is a diabetic, will fly to a U.S. military hospital in Wiesbaden, West Germany, for medical treatment in the next few days, L. Paul Bremer, U.S. ambassador for counter-terrorism, said Tuesday.

Reagan, in an exchange with reporters, did not explain how Singh's freedom was obtained. But he again ruled out any U.S. deals with the captors, believed to be an pro-Iranian Islamic group.

He said trying to secure the release of the nine Americans held in Lebanon "has been a great problem for us and it's very much on our minds."

Reagan declined to speculate on what move the United States might make to win the release of the nine American hostages.

"We've done no negotiating on that at all," he said, "and I'm not going to hazard a guess as to why they turned him loose _ not as long as we've still got hostages there," he said while posing for pictures with Republican congressional leaders in the Cabinet Room.

Asked if he thought Iran was attempting to manipulate the outcome of the U.S. presidential election, Reagan smiled and said, "Well, if they are, I hope they're on the right side."

Senate Republican leader Bob Dole, asked about the political implications, said, "I just hope for the sake of the hostages they are released today, without any reference to the election. Every day they stay there is another day of hell."

In an interview published today in The New York Times, the spiritual leader of a group believed to be an umbrella for captors of foreign hostages was quoted as saying it was "not yet the right time for the American hostages to be freed."

Sheik Mohammed Hussein Fadlallah, spiritual head of the Iranian-backed Hezbollah, or Party of God, also was quoted as saying the fate of the hostages "would have to wait for the outcome of the American presidential election." He said Iran preferred to deal with the Republicans.

Pressed to discuss what options are available for U.S. officials attempting to get the hostages released, Reagan said, "I can just tell you that this has been a big problem for us. It's something very much in our minds. . . . I just can't talk any further about it."

In a prepared statement read earlier in the day to reporters, White House spokesman Bob Hall said, "We are pleased at the announcement that Mr. Singh has been freed by his captors.

"Our pleasure at his release is tempered by the knowledge that nine innocent Americans are among those still held hostage in Lebanon."