Nicaraguan President Daniel Ortega said today that President Reagan's latest attack on the Sandinista government was an attempt to keep alive a policy of military force that could lead to direct U.S. military intervention in Nicaragua.

Ortega, in a speech before military personnel, their families and journalists, quoted Reagan's comments at a Washington news conference Thursday calling the Sandinistas a "communist, totalitarian" regime.

Reagan argued that the Congress should renew aid to anti-Sandinista rebels until the Sandinistas "cry uncle" and change the structure of their government. Reagan's statements were regarded by observers here as some of the strongest language he has used against the five-year-old Nicaraguan government.

"The president of the United States is on an absolute crusade, an absolute campaign to defraud, to pressure the United States Congress," said Ortega.

But Ortega said Reagan's request that the Congress grant $14 million in funding for the contra rebels, which has been held up since the fall, was not the main issue.

"The U.S. government has found other ways to send that money," he said, "through third countries and through fake organizations that the CIA has created in the United States." Ortega gave no details on these accusations.

"The question is to find support for his entire policy, not just find the $14 million," said Ortega.

He said his government believes that policy may include a plan by which the United States will recognize a government in exile, led by such figures as former Sandinista junta member Arturo Cruz and former codirector of the opposition newspaper La Prensa, Pedro Joaquin Chamorro, both of whom are in voluntary exile.

Ortega said he expected that the United States would recognize such a government immediately and aid it militarily.

He also said he believed that if the Congress votes to renew aid to the contras, that Reagan would interpret that as support for his use of military force against Nicaragua, "and in those circumstances you could expect the eventuality of direct U.S. military intervention in Nicaragua."

The Nicaraguan president said that if the Congress votes against the $14 million appropriation, "the president would have to take into account what the Congress decided, and there would be, perhaps, better conditions for a negotiated political solution."

The Sandinista leaders long have insisted that the administration is attempting to overthrow them, and officials here say that current U.S.-Honduran military maneuvers in neighboring Honduras are part of preparations for an eventual U.S. intervention in Nicaragua.

The maneuvers began earlier this month and are scheduled to last until April. They will include about 4,500 U.S. military personnel, some of whom will be deployed in tanks near the Honduran-Nicaraguan border.

Meanwhile, in Washington today, the Nicaraguan Embassy disputed Reagan's news conference assertions that the rebels, whom the president describes as "freedom fighters," principally are disaffected former supporters of the Sandinista revolution. In a statement, the embassy said "the leaders of the contras fought to sustain the [Anastasio] Somoza dictatorship in Nicaragua, and when they failed in that effort they fled the country and were reorganized, trained and financed by the CIA."