Ronald Reagan's top advisers have decided that the Republican presidential nominee should not participate in any further debates in this campaign.

The strategic decision reflects a cautious optimism among his advisors, based on private polls that show Reagan leading President Carter. In effect, Reagan has decided not to risk this lead by debating the president.

This was the reason Reagan rejected the latest offer from the League of Women Voters calling for a head-to-head debate with Carter followed by a three-way debate including independent candidate John B. Anderson.

But while refusing another debate, Reagan and his advisers intend to try to blame the White House for any failures to reach agreement on future debates.

"Carter's zigs and zags on debates, starting with Teddy Kennedy, have already made him a credible complainer on this issue," said one Reagan aide.

But the circumstances of Reagan's rejection of the league offer Thursday suggest that his advisors recognize he may have his own public relations problem with the decision. That announcement was carefully timed for late Thursday night to minimize news coverage.

White House officials today jumped on Reagan's decision as proof that the GOP nominee, in the words of White House press secretary Jody Powell, "is willing at this point to go to virtually any length to avoid a one-on-one debate with the president."

Asserting that Reagan's "cloak of self-righteousness" had been stripped from him, Powell said in Washington: "He claimed to base his decision on concern for Mr. Anderson. That seems to be a rather transparent position on Governor Reagan's part, in as much as Mr. Anderson has accepted the [league's] proposal."

Powell said the decision "very clearly lays bare" the attitude of Reagan and his advisors -- "they have been attempting to hide behind Mr. Anderson to avoid a face-to-face debate with the president . . . Their duplicity is obvious in the extreme."

Arriving in Los Angeles this afternoon, Reagan insisted that he was not refusing to debate at all. He said he was merely being consistent in insisting that Anderson be treated equally.

"If he [Anderson] was a viable candidate when he had 15 percent, why isn't he when he has 19 percent?" Reagan said. Reagan's advisers decided early Thursday not to participate in any further debates in this campaign, but no announcement of the decision was made on the Reagan campaign plane as the candidate flew from San Jose, Calif., to Seattle.

Press spokesman Lyn Nofziger sent an aide back on the plane with a "no comment" when reporters asked how Reagan intended to respond to the league proposal for a Carter-Reagan debate followed by a three-candidate forum.

In Seattle, reporters asked Nofziger directly and were told: "I don't know. I can't tell you. I've got no answer for you yet." On the airport runway, as the plane departed for Portland, Ore., Nofziger said, "We have no idea what we're going to do yet."

Nofziger again declined to talk to reporters on the flight to Portland. But when the plane arrived there, Reagan read a statement rejecting the league proposal and refused to answer any questions about it.

The timing of Reagan's statement meant that the rejection of the debate was not carried on the late evening television news shows and also that it missed all except the late editions of Eastern morning newspapers.

Reporters for the wire services accompanying Reagan also were delayed on their entrance to the Portland hotel where they filed their stories. Reagan aides attributed this to a mix-up involving local staff members and security forces and said it was not part of any effort to delay filing.

The Reagan strategists' actions are reminiscent of the White House strategy a few weeks ago when the president's negotiators were simultaneously dodging the debate while proclaiming Carter's willingness to face Reagan. The reasons in both cases are tactical political ones. The White House doesn't want to do anything that would enhance the Anderson candidacy. The present Reagan view is that the GOP nominee is ahead and doesn't need a debate to defeat Carter.

In Washington, Powell predicted, as have other Carter aides, that Reagan will change his mind before the election and agree to debate Carter alone for his own political good. He also repeated the White House pledge that the president will participate in a three-man debate involving Anderson after he debates Reagan.

From the beginning of the dispute over the debates, Carter strategists have gambled that the League of Women Voters, faced with the prospect that there would be no debates this year involving the incumbent president, would cave in on its insistence that Anderson be included and agree to sponsor a Carter-Reagan confrontation. On Thursday they won that gamble, which for the first time took the Carter campaign off the defensive on the issue and allowed it to portray Reagan as the man afraid to defend his record.

"I think we can get a good week to 10-day ride out of this," said one Carter strategist of the plan to exploit the new equation in the "debate over the debates."

Reagan insisted again today that he is willing to debate the president. But his strategists continue to believe that the best tactic is to insist Anderson be given equal footing because in polls Anderson takes more votes from Carter than he does from Reagan.

When Reagan was asked in Portland this morning whether there would be any debate with Carter, he replied, "That's up to him."

But it is now the hope, belief and strategy of the Reagan forces that there will be no more debates with anyone.