Nicaraguan President Daniel Ortega, responding to the congressional approval of $100 million in aid to Nicaraguan insurgents, tonight called President Reagan "a new Hitler" and warned of the eventual "Vietnamization" of the Central American conflict.

The Sandinista leader, speaking at a press conference aired on national radio, warned that if U.S. advisers trained insurgents, known as counterrevolutionaries or contras, in Honduras they would "run the same risk as the mercenary forces." He called the $100 million aid package an "escalation" of the U.S. "interventionist" policy.

But the president did not indicate that any unusual action would be taken in response to the vote.

He said that Reagan is "acting like a new Hitler . . . with a terrorist policy, a policy of assassinating women, children, the people of Nicaragua," and he warned that the aid would lead to U.S. military intervention in Nicaragua.

Ortega called the vote a blow to efforts by the Contadora group of Mexico, Panama, Colombia and Venezuela, which is attempting to find a negotiated solution to the Central American conflict. He also warned Nicaraguans that increased aid to the contras would mean more serious economic problems inside Nicaragua which would require more sacrifice.

But he said, "the people of Nicaragua are not going to surrender to . . . this terrorist policy."

In Tegucigalpa, Honduras, contra leaders rejoiced over the House vote, saying it gives them "moral support" in their war against the Nicaraguan Sandinista government.

"There is much happiness in the troops," Carlos Icaza, chief lawyer for the Nicaraguan Democratic Force, told United Press International.

"This brings us enormous happiness because it not only means economic support but shows that the members of Congress have opened their eyes to the danger of the Soviet invasion of Central America," he said, echoing Reagan's warning of Nicaragua possibly turning into a Soviet base.