There has been a lot of pressure on the Reagan administration to negotiate in Central America, but few specific ideas on how or what to negotiate. Here's a proposal.

Besides improving the Salvadoran armed forces, the strategy of the Reagan administration and the Salvadoran government relies on elections. The left is invited to participate or to talk about the elections in the Peace Commission. The left (FDR/FMLN) says that elections under the government's auspices would be meaningless at best; more likely, they would be suicidal. Even if bodyguards would protect rather than "terminate" leftist candidates, who would ensure the results? So the left proposes "negotiations without preconditions" as a way to resolve the conflict, and the government, interpreting this proposal rather liberally and disingenuously as a demand for power-sharing, blocks negotiations. The war grows worse, and there is little prospect that the government's elections will discourage the guerrillas or reduce the rightist violence. The elections could provide a modicum of legitimacy to the government, but if the right wins the election, that won't last long or be worth much.

There is room enough and reason enough to compromise. War strengthens extremists, particularly in countries like El Salvador where the middle--both moderates and the spirit of moderation--is precarious and democracy is embryonic. Only at the bargaining table can moderates on both sides be put in a position where they could begin calling the tune rather than dancing to it or running from it.

Instead of elections without negotiations or negotiations without elections, why not wide-ranging negotiations leading to elections? Both sides --and the Reagan administration--should announce their support of the following compromise proposition: "Elections remain the best way to test the will of the people, but they are impossible in the current climate of violence. Negotiations should begin immediately to define the terms and the conditions that will permit the elections to be free and fair and, if possible, held in December 1983." "Terms and conditions" could be defined broadly enough to include the reorganization of the military, guarantees on electoral results, an interim government--whatever; the point is that the conditions for free elections would be negotiated without preconditions, thus satisfying the current position of both sides.

Who can refuse such a proposition and retain international credibility? Having insisted that elections are the "political solution," the Reagan administration can hardly reject honest negotiations aimed at making the elections fair. Having asked to talk about a reorganization of the military and a provisional governing structure as a way to guarantee the rights of the left, the FDR/FMLN can hardly retreat, without implying its opposition to elections in principle. Certainly, the Christian Democrats, who have their own good reasons to fear that the right will erase them either during or after the election, should welcome negotiations that guarantee their safety and return them to the middle of the Salvadoran political spectrum where they belong. The right will participate in negotiations only if the Reagan administration can persuade them that they have no alternative. Failure to apply U.S. leverage on the right will doom negotiations from the beginning.

Assuming the proposition is accepted by the government and the left, both sides would issue an invitation to international "sponsors" to oversee the negotiations, the elections and the outcome. The Contadora Group should be the principal sponsors, but it should be expanded. One idea would be for the left to be sponsored by Mexico, Spain, France and Colombia, and the government to be sponsored by the United States, Venezuela, Panama and the Dominican Republic. Representatives of these countries would sit at the bargaining table and play an active, facilitative role in the negotiations and in implementing an agreement of eight points.

1. For purposes of building confidence and trust as much as for stopping the war, the first item on the agenda should be the negotiation of a cease- fire, say for one day in one area. As negotiations proceed, the cease-fire should be extended over time and space.

2. Both sides would negotiate a two-month electoral period, in which all parties would register and participate and have equal access to the media. An electoral board would be broadly representative of both sides and would oversee the election, assisted by a large number of international observers. To dispel suspicion, the Reagan administration would state clearly that it would fully re- spect the outcome if the Communists won the election. Parallel statements could be solicited from other sponsors and also from Cuba and the Soviet Union.

3. Both sides would agree to a constitution, which would make minor modifications of the existing one, but would in stitutionalize the land reform (phases I and III), guarantee economic and political pluralism and pledge a nonaligned foreign policy.

4. During the electoral period, the armed guerrillas would stay in their camps, and the military would cease operations in these areas--thus reducing and ultimately ceasing military contact. Security would be guaranteed by an "election-protection peace force" composed of soldiers from most or all of the eight sponsors. This force would remain in place for at least three months after the elections in order to ensure continuity and guarantee the results.

5. Both sides would accept some responsibility for the repression--the killing of innocent civilians--and, supervised by the peace force, would dissolve the most repressive elements of both forces, say, the government's Treasury Police and National Guard and the two most brutal of the five guerrilla armies.

6. A plan for integrating the guerrillas into a reorganized armed force would be negotiated and would come into force two months after the election and one month after the inauguration of the new government.

7. A negotiated interim government would come into being at the signing of the agreement and the beginning of the electoral period. This interim government would give representatives of the various groups the first opportunity to communicate directly with one another and to work together. It would also preclude government assistance to any party.

8. The sponsoring nations would agree to contribute a total of $2 billion in economic aid directly (and encourage another $2 billion by other donors) for a five-year period to help El Salvador recover, implement the reforms, and contribute to a rejuvenated Central American Common Market. It is well to recall that before the war, El Salvador demonstrated its capacity for economic growth (5.3 percent per year sustained over 20 years), social progress (the distribution of income improved from 1965 to 1977) and expanded education. With outside help and inside peace, El Salvador could be a economic engine for Central America.

In addition, the sponsors would agree to provide $50 million in military aid during the same five-year period, but all economic and military aid would be negotiated directly and exclusively with the civilian government and would be turned on or off by the civilians, or off by the sponsors if the military should interfere with the government. It is essential that in the postwar period, all outside democratic governments do everything they can to keep the military out of politics.

These are the rough and radical elements of one peace plan. It is offered not as the only plan but only to demonstrate that if the administration used half as much energy in pursuing negotiations as it does in trying to get Congress to fully fund its military aid program, hundreds of possible variations would suggest themselves.

Negotiations will not be easy, and no one should expect that all those on the left or right will remain a part of the process; they won't. However, it is essential to test the sincerity of both groups and to divide those who want democracy from those who only want power. The aim is to narrow the base of those who prefer fighting to compromise, rather than to squeeze the middle, which is the consequence of the current strategy. The government that emerges from negotiations will be able to stand on its own and fight the remaining guerrillas from real strength--not the kind that comes from guns, but the kind that comes from popular support.

If this negotiation succeeds, the same formula could be applied to Nicaragua. The same eight- nation sponsors could oversee a negotiation between the Sandinista government and the rebel groups. If the Sandinistas believe that their revolution is worth exporting to El Salvador, perhaps they can be persuaded to import a solution for peace from their neighbor and Common Market partner.

While the Contadora Group endlessly debates the shape of the negotiating table, and the Reagan administration insists on regional rather than bilateral talks, this proposal cuts through the Central American knot by going to the real source of the problem, which is not external support but internal division.

The best part of this plan is that everyone is welcome to take the first step; there is no reason why Spain, the Socialist International, the Contadora Group or the Salvadoran government should wait for the Reagan administration. The administration is hardly alone in making negotiations more difficult; this proposal offers everyone the chance of making them more likely. Spain, for example, could announce support of the first proposition and try to persuade the FDR/FMLN to accept it as well. By doing so, the burden would be passed to the Salvadoran government and the Reagan administration to accept full-scale negotiations on elections.

The administration has found a hundred disingenuous reasons to reject negotiations, but the Salvadoran left is not the Vietcong. It is an extremely heterogenous group, which includes disaffected Christian and Social Democrats, and quite possibly the only thing holding them together is the war and the absence of negotiations. Because the sponsors are democratic countries and the negotiator of the left might well be Guillermo Ungo, the Social Democratic leader of the FDR, the United States and its friends are better positioned to take advantage of negotiations than is the left. For that reason, I hope President Reagan takes the first step. Congress is right to insist on it.

Only through such a plan can the divisions that are opening in our country and have already opened between the United States and our friends begin to be healed. Most important, for El Salvador, it is vitally important that the action move quickly from the battlefield to the bargaining table before culminating at the ballot box.