TEGUCIGALPA, HONDURAS, FEB. 4 -- The defeat in the U.S. Congress last night of a Reagan administration aid package for the Nicaraguan rebels gives the Sandinista government a major psychological victory and risks putting increased pressure on Honduras, according to the contra military commander.

"It isn't what we wanted, of course," said the rebel commander, Enrique Bermudez, with a tone of resignation. He added, however, that he had consulted a number of his field commanders inside Nicaragua and that they were unanimous in agreeing to continue the six-year-old war.

"This is like losing a battle. We have not lost the war," Bermudez said.

In an interview at a location in Central America that he did not wish to be revealed, Bermudez said, "We are in a struggle for democracy in Nicaragua, and we haven't achieved this goal yet. The causes that made us take up this struggle have not disappeared yet. We have taken a decision to continue the struggle."

He said the vote would have a severe impact on the logistics of the rebels, known as contras, and "a psychological impact in favor of the Sandinistas."

The U.S. House of Representatives rejected, by a 219-to-211 vote last night, President Reagan's request to provide $36.2 million in new aid to the contras. Bermudez charged that Democrats in the House -- 207 of whom voted against the aid, along with 12 Republicans -- did not realize "the totalitarian nature of the Sandinistas," and he rejected the idea that future humanitarian aid for the contras could be delivered through neutral organizations, such as the Red Cross.

"I don't think it will be appropriate for us to accept" such aid, he said.

Honduran President Jose Azcona, whose country harbors rear bases and logistical centers for the contras, declined comment today on the defeat of the contra aid.

A spokesman, Marco Tulio Romero, said Azcona viewed the congressional vote as an internal U.S. matter and would have no comment on its impact on Honduras.

However, in remarks yesterday before the House voted, Azcona indicated that he shared the administration's view that approval of new contra aid was needed to maintain pressure on the Sandinistas to negotiate with the rebels.

In another development, Honduran newspapers reported today that the chief of the Honduran Armed Forces, Gen. Humberto Regalado Hernandez, wrote a letter Tuesday to House Speaker Jim Wright (D-Tex.) in which he expressed the military's "deep worry" over events connected with the Central American peace process, but stopped short of an outright appeal for approval of the aid.

For Honduras, the rejection of the contra aid raises the prospect that armed Nicaraguan rebels will stream across the border into southern Honduras, causing problems for the Honduran military and civilian inhabitants. The contra military commander, Bermudez, estimated that most of the 16,000 fighters whom he claims to have under his command would continue the struggle, but that as many as one-third would quit over the rejection of new aid.

A study by American researcher Joseph Eldridge, a consultant to the human rights group Americas Watch, estimates that most of the contra forces, which he puts at between 8,000 to 12,000 fighters, would flee to Honduras and Costa Rica as a result of the aid cutoff.

Eldridge said the Honduran Army was likely to draw the conclusion from the vote that "the U.S. is reneging on its responsibilities." In return for permitting the contras to use Honduran territory, he said, "the Hondurans expected the White House to win the political battles and continue to support the contras, a policy from which they derive considerable financial benefit."

In an interview in Central America last night, contra spokesman Bosco Matamoros said rebel leaders had contingency plans to deal with the aid vote setback, but declined to discuss them.

Matamoros said the contras would continue to fight, defying predictions that a new aid cutoff would cause them to disband.

"Our existence is not the result of a decision by the U.S. Congress," he said.

He said a "coherent U.S. policy" was necessary to keep the Sandinistas at the cease-fire negotiating table, but that the United States had proved an unpredictable ally.

Matamoros added bitterly, "U.S. aid has not made people willing to risk their lives for democracy. Dollars you can reprint, but not the lives of Nicaraguans who are fighting to be free."

Special correspondent Jake Dyer reported from San Jose, Costa Rica:

President Oscar Arias, author of a regional peace plan, called the U.S. congressional rejection of new contra aid "a vote of confidence both for Costa Rica and for those countries that have urged this dialogue, this negotiation to settle conflicts with our Central American brothers."

"From here on forward we will bury war," Arias said. "There will not be excuses or pretext not to comply faithfully with the principle and the letter" of the peace plan signed in August by the five Central American presidents.

{In Miami, Nicaraguan rebel leader Adolfo Calero said in reaction to the contra aid vote, "We have taken this kind of blow before and we have survived, and we are going to survive again," the Associated Press reported. Contra supporters held meetings to discuss a private fund-raising drive.}