Nicaragua's long-feuding anti-Sandinista groups are taking a first tentative step toward unification, Nicaraguan exile sources say. Such unity, if achieved, would improve President Reagan's chances of persuading Congress to provide money to the contras fighting Nicaragua's Sandinista government, say knowledgeable United States congressional observers. Top exile leaders plan to meet this week to iron out the details of a ``declaration of principles'' of their economic and political goals for Nicaragua. They hope to publically announce the agreement by Feb. 15, exile sources say.
In the short run, unification of these anti-Sandinista groups would confer chiefly political, rather than military, advantages on the exiles. The main advantage would be the marriage of the political respectability of civilian opposition leader Arturo Cruz Porras with the military resources of the Honduras-based contra rebels. It would mark the first time civilians like Mr. Cruz would be identified with the policy of armed fighting against the Sandinistas.
If the contras -- whose reputation among some US congressmen is marred by association with followers of former Nicaraguan dictator Anastasio Somoza Debayle -- ally themselves with someone of Cruz's stature, it would be more difficult to describe them as pro-Somocista. This factor would be of significance to Congress, which is expected to take up the issue of funding for the contras in late February or March. It might also result in more respectability in the international community.
Most knowledgeable observers say the opposition, even if united, could not by itself overthrow the Sandinistas. But in the long run a united opposition could help provide a political and military base for overt US armed intervention, if Reagan chooses that route, they say.
The declaration to be charted at this week's meeting will be the first step toward forming a political action committee of top exile leaders, say some of those involved.
``This committee will have most characteristics of a government in exile without officially being called a government in exile,'' says one high-level exile source.
The tentative agreement represents a dramatic turnaround in the positions of Arturo Cruz Porras and Ed'en Pastora G'omez, who have previously resisted CIA pressure to unite them with the Honduran-based contras.
This document, according to one high-ranking Nicaraguan exile politician, is basically a declaration of the kind of government which the opposition would eventually like to see in Nicaragua.
It was ``carefully designed'' to provide ``something for everyone, something everyone can agree with, be it the FDN [rebels] on what you would call the right, and Robelo, Pastora, and Cruz on what you would call the left,'' says one exile.
Top anti-Sandinista leaders who are expected to sign the declaration are Mr. Cruz, a politically liberal former member of the Sandinista junta who was almost the candidate of a united opposition in Nicaraguan elections last November; Alfonso Robelo, a moderate businessman who is a leader of the Costa Rican-based armed opposition group, Democratic Revolutionary Alliance (ARDE), and also a former member of the Sandinista junta; Mr. Pastora, a former Sandinista war hero who deserted to the opposition; and Adolfo Calero, head of the Nicaraguan Democratic Force (FDN), the Honduran-based contras whose top military leadership is dominated by Somoza followers.
The main military corps of anti-Sandi- nista fighters is Mr. Calero's FDN, which is estimated to number some 8,000 men. Somocistas control the FDN's top military command and retain key positions in its political structure, which often results in press descriptions of the FDN as ``the Honduran-based pro-Somocista contras.'' But ``Somocistas'' do not constitute a majority of the troops of lower military rank.
There will be little immediate military impact in the unity move, since the bulk of anti-Sandinista troops in Honduras and Costa Rica are already in FDN hands. But unity could eventually bring Pastora's Costa Rica-based troops under a joint command. And if forces in the south are greatly strengthened, a united command could be of help in any military pincer strikes against the Sandinistas.
Some exile sources told the Monitor that anti-Sandinista leaders hope that the coalition could be used as a base for eventually diplomatically isolating the Sandinistas in the way Somoza's regime was isolated in 1979. (The Sandinistas overthrew Somoza in July 1979.) Some exile leaders hope to persuade the Organization of American States to censure the Sandinistas as it did Somoza.