MANAGUA, NICARAGUA, AUG. 2 -- Nicaragua is proceeding with preparations to receive Soviet-made MiG fighter jets and will feel more justified in importing them if the United States, as planned, supplies F5 jets to Honduras, Defense Minister Gen. Humberto Ortega has announced.

Managua's two dailies, which are government-controlled, this morning reported statements made Saturday by Ortega, the top military commander, at a ceremony marking the eighth anniversary of the Sandinista Air Force.

Ortega stressed that Nicaragua requires the MiGs to intercept CIA-run air resupply flights from Honduras and El Salvador for the U.S.-backed rebels, known as contras. Sandinista intelligence detected 20 supply flights in July alone, the general said.

The MiGs would bolster Nicaragua's defenses against the contras and any direct U.S. military intervention, and would not be used to attack neighboring countries, Ortega asserted. But he added:

"To the degree that the U.S. continues to arm Honduras with weapons like the F5, it undoubtedly makes it more possible and more justified for Nicaragua to obtain the interceptor jets we need."

Ortega's sharp warning that his forces continue to make ready for escalating warfare appeared to signal Nicaragua's pessimism that Central America's five presidents will achieve any important results at their peace summit in Guatemala Thursday and Friday.

For more than two years, Sandinista leaders indicated they were not making immediate moves to introduce MiG aircraft, although they asserted their right to do so. The United States has threatened to respond with direct military action to destroy the Soviet fighters if the Sandinistas bring them in.

This weekend, Ortega, discussing preparations and crews for the MiGs, said, "We have the airfield, we have the men." He added that Nicaragua has not brought the planes in until now primarily because of technical preparations, including installation of advanced navigational systems and completion of airport facilities.

"But this doesn't mean we aren't basically prepared to handle them," Ortega said. "Fundamentally we are overcoming those problems."

The Reagan administration approved the $60 million F5 sale to Honduras late last year to replace an aging fleet of French-built Super Mystere jets. Honduras, which has the most advanced Air Force in Central America, is not expected to pay cash. Delivery of the first F5s is expected before the end of this year.

The Pentagon said the F5s would not escalate the weaponry in the region because they were replacing an older but roughly equivalent aircraft. The F5 was produced for sales to U.S. allies in the 1960s and is not considered a first-rank fighter.

Sandinistas have decried the planned sale of F5s as altering the military balance and some Pentagon officials also have said that it could prompt a confrontation with Nicaragua over the MiGs.