A sharply partisan debate erupted last night about President Reagan's news conference comments on his Central American policy, with Democrats condemning his rhetoric as a step toward war and Republicans insisting that he had made it clear that his actions are aimed at peace.

Several Democratic presidential hopefuls and third-party aspirant John B. Anderson teed off on Reagan in unusually sharp language.

Former vice president Walter F. Mondale said it was clear that "he is on a course that will lead us into war."

Most Republicans, however, pronounced themselves pleased, with Sen. Richard G. Lugar (R-Ind.), chairman of the National Republican Senatorial Committee, describing Reagan's comments as "positive and reassuring."

Majority Whip Ted Stevens (R-Alaska) agreed.

"As far as I'm concerned the president is on the right course," he said. "We place very high on our priorities the stability of Latin America. We're not going to countenance the overthrow of governments down there with Warsaw Pact arms."

Two key Republican moderates, Sens. Nancy Landon Kassebaum of Kansas and Sen. David F. Durenberger of Minnesota, broke with the party line to express misgivings about Reagan's remarks.

"I don't believe the president particularly answered the questions that are out there," Kassebaum said. Durenberger, in a separate interview, said it was unclear "how far he is willing to go to accomplish what end."

Durenberger also said that "once the president became so personally involved" in defending his policy, "he raised the stakes to the most important political issue facing the country."

Anderson and the Democratic presidential aspirants seemed eager to give it that sort of prominence by making it a sharply partisan issue.

After the news conference, the House defeated an effort to prohibit Reagan from deploying troops in Central America, even for military exercises. It rejected, 259 to 165, an amendment to the defense authorization bill by Rep. Edward J. Markey (D-Mass.) that would have prohibited deployment of American troops in El Salvador, Nicaragua, Honduras, Guatemala or Costa Rica, except with the permission of Congress or if the United States or its citizens were in immediate danger.

The hour-long debate on the Markey amendment to prohibit deployment of troops was emotional and made frequent reference to Vietnam.

"We are now on the brink of an era which very much resembles 1965," Markey said.

"We hear echoes in this chamber tonight of Vietnam," Rep. Barbara Boxer (D-Calif.) said. "And with the appointment of Mr. Henry A. Kissinger to the president's commission on Central America, we see ghosts of Vietnam. If there is anything we vowed when we came to this House it was never to be involved in repeating that mistake [Vietnam] again."

"This is a foreign policy issue and there is nothing new about sending down fleets to Central America," said Rep. Samuel S. Stratton (D-N.Y.). "A demonstration of our capabilities will probably convince the Nicaraguans that they ought to pull in a little bit."

Sen. Alan Cranston (D-Calif.), another presidential candidate, said Reagan simply was trying "to put a peaceful gloss on military moves" and pursuing a policy that faces "rising opposition in this country."

Anderson, the 1980 independent candidate who is heading an embryonic third-party movement for 1984, said Reagan was offering "confrontation without clarification," and said that, listening to the news conference on a car radio, he thought it was "the most defensive performance . . . since he became president."

Mondale said Reagan had "failed to reassure the public, and since the whole purpose was to do so, the vagueness in itself is suspicious . . . When a president sends 4,000 troops into a war zone," he said, "it is not enough to blame it on the press."

A sampling of party chairmen in various sections of the country showed a similar split in perspective.

"The majority here are not worried about a war breaking out in Central America," said Don Adams, Illinois GOP chairman. "We're worried about the heat wave and the corn crop."

John Holmes, Rhode Island Republican chairman, said, "I don't know what else a president could do to dispel the fear of military escalation." His counterpart in Wyoming, Fred Schroeder, called it "an honest try to set to rest the idea that he is trying to foster a situation that could lead to war."

Democrats, predictably, were more critical. "I don't think he did anything to allay the growing feeling people have that we are inching closer to some kind of confrontation," said Richard Weiner, Michigan Democratic chairman. "In fact, I think it will increase it."

"It was not a confidence-building speech," said New Hampshire Democratic chairman George Bruno.

South Carolina Democratic Chairman W.J. Bryan Dorn said that most voters in his region worry that "Central America may gradually become like Cuba," but said Reagan's "bumbling performance . . . did not build the enthusiasm and confidence we need to stop that from happening."

For the most part, members of the president's newly named bipartisan commission on Latin American policy stood aside from the partisan exchange over his press conference.

"I don't think the questions or the answers produced much," former Democratic National Committee chairman Robert S. Strauss said. Former senator Nicholas F. Brady (R-N.J.) said it would be "ill-advised" to comment on day-to-day policy developments when the commission was chartered to frame long-term policy.

Dr. John Walsh said he thought "the president made himself quite clear on his thinking," adding that he agreed that security measures went hand in hand with long-term economic development plans.

"Industry cannot develop where plants are being blown up," Walsh observed.

The most critical comments from any of the commission members last night came from San Antonio Mayor Henry Cisneros, a Democrat. He said "our well publicized military presence in the region is not conducive to the success" of diplomatic efforts being pressed by Latin American countries or by Reagan's special envoy, former senator Richard B. Stone (D-Fla.).

"My own position," Cisneros said, "is that a clear signal about our desiring to be part of the peace process would be better served by not coupling them with military activities at this time."