Truce Is Over, Ortega Declares : Nicaragua: He vows to drive out the Contras. He also calls for peace talks, but their resumption is uncertain.

MANAGUA, Nicaragua —  President Daniel Ortega formally ended a 19-month-old cease-fire against U.S.-backed rebels Wednesday and said the Sandinista army will try to push them back to bases in Honduras. But he asked rebel leaders to meet in New York next Monday for talks on ending the newly resurgent Nicaraguan war.

Enrique Bermudez, the senior Contra commander, said he will accept the offer if Nicaragua’s Roman Catholic cardinal is also invited, a condition that Ortega quickly accepted.

The collapse of the cease-fire plunged this war-weary country into its deepest period of uncertainty in two years of peace efforts. Cardinal Miguel Obando y Bravo appealed for “restraint and maturity” by both armies, warning that intensified fighting could disrupt the elections scheduled next Feb. 25.

A resumption of peace talks, broken off in June, 1988, is far from certain. Ortega insisted that Honduras be represented, but that government balked at agreeing to go. U.N. Secretary General Javier Perez de Cuellar, the would-be host, was described by aides as surprised by Ortega’s announcement and would not confirm that a meeting will take place.

“This is extremely unusual,” a U.N. official said in New York. “It might have been easier if (the Sandinistas) had notified us first. There’s a furor up here over the breakdown of the cease-fire. Now they are calling a meeting on how to disband the Contras at the same time they are going back to war. I’m not very optimistic.”

Ortega proposed the talks during a 6 a.m. press conference that was broadcast live so that Nicaraguans could awaken to the news that the cease-fire is over. Citing growing rebel violations, Ortega had threatened last week to let it lapse at the end of October.

He said he hopes the talks will bring diplomatic pressure on the Bush Administration to support an agreement among the five Central American nations to “demobilize” the Contras by Dec. 5 and assure a peaceful election campaign.

That Aug. 7 accord, signed at Tela, Honduras, called on Washington to divert what is left of the Contras’ $48.9-million allotment of non-lethal aid to a fund to ease their return to civilian life in Nicaragua or elsewhere. The Bush Administration and congressional leaders have said they will continue the aid to maintain the Contras as an army-in-waiting through the election.

“We do not want a cease-fire; we want an end of the war,” the Sandinista leader declared. Because of rebel violations, he added, “a cease-fire means that the war is still present.”

Ortega, in a later interview with four American reporters, said the 70,000-member Sandinista army will pursue the Contras more aggressively, reinforce vigilance along the Honduran border to halt rebel infiltrators and put “thousands of Nicaraguans” under arms to protect their own farming cooperatives from rebel attack.

He said 1,100 of the 7,000 or more Contras who were camped in Honduras have crossed over into Nicaragua in the past three weeks, joining another 2,000 or so already deployed along this country’s central mountainous spine. The Contras claim to have 6,000 troops in Nicaragua.

The Sandinista army will abide by a promised suspension of military conscription until after the election, Ortega said, but will not rule out the use of long-range artillery or helicopter gunships--weapons not used during the cease-fire--if rebel forces congregate in large groups.

Another Sandinista official said such an escalation of firepower is economically costly and therefore unlikely.

“The new policy will give (Sandinista ground forces) more freedom to push the Contras away from the cities, toward Honduras and the Atlantic coast,” he said, admitting that such operations had already begun. “But the war will not change dramatically.”

In Tegucigalpa, the Honduran capital, the Contras charged late Wednesday that Sandinista forces had attacked rebels inside Nicaragua with heavy artillery hours after Ortega suspended the cease-fire, United Press International reported.

The rebels said the Nicaraguan troops used helicopters, air-to-ground missiles and heavy artillery in several provinces, including Zelaya Central, in the central part of the country 50 miles north of Managua. There was no immediate confirmation or reaction from Managua.

Contra leader Bermudez said the rebels will not formally renounce their part of the cease-fire. He said they will use “evasive tactics” against stepped-up Sandinista pursuit. Speaking in Tegucigalpa, Honduras, he appealed to the United States, which cut off arms aid early last year, “to give us enough to defend ourselves.”

Noting the risk of such a move, Vice President Sergio Ramirez said “this would throw more fuel on the fire. . . . This would end the electoral process.” Later, Ortega clarified that remark, saying elections will take place in any event.

Opposition leaders said Ortega was using insignificant skirmishes in remote areas to create an excuse to cancel the election if it appeared that his revolutionary party, in power 10 years, would lose.

“The Sandinista Front fears the political process and prefers war,” said Alfredo Cesar, a former Contra leader who returned from exile this year to help run the presidential campaign of opposition candidate Violeta Barrios de Chamorro. “They are creating conditions to return to open military conflict, the only thing they know how to manage.”

After six years of fighting, the Sandinistas and Contras agreed to a cease-fire March 23, 1988, and opened political negotiations on a final armistice. Although those talks collapsed three months later, each side unilaterally agreed to refrain from offensive military operations.

In practice, the Sandinistas have maintained their patrols, trying to keep the rebels on the move and away from major towns. This has provoked periodic armed encounters. While the bulk of the rebels retreated to Honduras, those remaining behind have used their dwindling ammunition in selective ambushes aimed at seizing Sandinista arms.

Still, the fighting has been reduced dramatically from its peak level in 1987, when the Sandinista army reported an average of 15 clashes per day and as many as 150 dead government soldiers per month.

In the five months from May to September this year, for example, the Contras admitted losing 114 soldiers and the Sandinistas admitted losing 81 in an average of three clashes a day.

However, the Sandinista army reacted with alarm after stepped-up rebel attacks in October killed 48 government soldiers, 18 of them in a single ambush--the army’s second-costliest month of the cease-fire. The attacks disrupted voter registration in some rural areas.

Ortega’s first announcement that he would end the cease-fire came last Friday during a Pan-American summit in Costa Rica. The next day, amid criticism from President Bush and others present, he backed away slightly, saying he would maintain the truce if U.S. aid to the rebels were tied to their disarmament.

In a subsequent flurry of diplomatic activity, Ortega met here with Argentine President Carlos Saul Menem and telephoned the Rev. Jesse Jackson in Washington to ask for help in dismantling the Contras. Sandinista officials said they decided Tuesday to end the cease-fire when it became clear that those efforts would not work immediately.

At his press conference, Ortega used some of his harshest language against the Bush Administration, Congress and the American press, accusing them of “cynicism . . . cowardice and immorality,” saying they ignored Contra violations while criticizing his government’s response.

“President Bush, we are not going to prolong the cease-fire,” Ortega declared in a voice rising in anger. “We are not a state of the United States. . . . The United States has no reason to dictate to the Nicaraguan people what they should do in the face of criminal attacks that it promotes.

“Even Christ lost patience and felt the right to take the whip to run the money-changers from the temple,” he added.

During the later interview, a calmer Ortega emphasized repeatedly that he was seeking a political and not a military solution to the war. He said ending the cease-fire is “a dramatic step” necessary to focus international attention on the Contra issue before “even more drastic steps” were forced on him.

“There is still time to save the situation,” he said, before the final stage of the election campaign begins Dec. 4.

Ortega said the proposed talks with Contra leaders in New York would be to “approve logistical and technical matters” to promote the rebels’ disarmament. But Bermudez said he will use the talks to demand substantive concessions, such as amnesty for more than 800 accused counterrevolutionaries imprisoned in Nicaragua.

Ortega insisted that the meeting should include Honduras and a commission representing the United Nations and Organization of American States that was set up to supervise the Tela accord.

But the Honduran government issued a communique Wednesday saying it saw no reason to attend.

BALANCE OF MILITARY POWER IN NICARAGUA

The Sandinista army, by far the largest in Central America, is well equipped for ground action, with much of the weaponry built in the Soviet Union. The army has about 140 tanks for its five armored battalions. A small air force with armored helicopters and a few propeller-driven combat aircraft and a navy of mainly coastal patrol craft complement the large ground force.

The Contras have shoulder-fired surface-to-air missiles in their arsenal. In spite of the U.S. cutoff of military aid, they are believed to have considerable stocks of explosives, small arms and ammunition. Nicaraguan government troops: 40,000 regulars and 30,000 reserves.

Contras: Rebel forces of 6,000 to 8,000 in and around the Yamales camp in Honduras. Another 3,000 to 6,000 rebels are across the border inside Nicaragua.