"We do not have to render accounts to anyone, and much less to those who are compaigning against us. . . . We don't have to tell anyone either if we're receiving tanks, planes, mortars, cannon," Defense Minister Humberto Ortega told a news conference today in response to reports in Washington that Nicaragua may have received sophisticated weapons from the Soviet Union.

Ortega refused to confirm or deny statements attributed in a Washington Post article June 2 to unnamed State Department officials that intelligence reports have indicated Soviet T55 heavy tanks may already have been oved into Nicaragua from Cuba, and that Nicaraguans are receiving military training in communist countries.

The Post story, and subsequent comments by Secretary of State Alexander M. Haig Jr. that Nicaragua is a "threat to the region," received front-page coverage in Managua's Sandinista newspaper as well as its two independent papers.

"We are strengthening our defense," Defense Minister Ortega said today, "and we are prepared to operate tanks, to operate planes, common and different kinds of weapons. Our combatants are ready to take up these arms . . . we know clearly that we must have tanks and cannon and different kinds of arms to defend our revolution."

The tone of Ortega's speech was clearly defiant. In recent weeks tensions between Nicaragua and neighboring Honduras' military government have risen to the point that, by some reports, Nicaragua prepared for invasion. Following a recent meeting between the two governments on their shared border, however, local attentio once again has shifted to the United States and what is perceived as its aggressive policy against Nicaragua.

"We see a real danger in all these demonstrations of the most reactionary centers abroad and of the United States against Nicaragua, on the economic and political level," Ortega said, in apparent reference to the recent U.S. decision to suspend the aid program here. "This campaign about the weapons could . . . justify more dangerous measures against Nicaragua," Ortega said.

While the United States sees the fast-growing Sandinista Army as a potential tentacle of Cuban and Soviet expansion, the Sandinistas, along with large sectors of the Nicaraguan population, present themselves as constantly under threat of a major military invasion, either by other Central American armies opposed to this country's leftist government, or directly by the United States.

"There is a real military danger," Ortega said today, "and it is our duty and right to arm our people to defend our nation and our revolution."