By John Goshko
Washington Post Staff Writer
Wednesday, December 23, 1998; Page A09

UNITED NATIONS, Dec. 22—State Department officials were deciding tonight whether to expel three Cuban diplomats attached to Cuba's delegation to the United Nations for alleged espionage activities in the United States, diplomatic sources said.

The sources said that the U.S. government notified the Cuban mission here late Monday that the United States tentatively plans to order the three to leave the country immediately. However, the sources said, the department gave the Cuban mission 24 hours to offer a reason why the expulsion of the diplomats, who were not identified, should be canceled.

That deadline passed this evening, and the sources said they did not know what reply, if any, Cuba had made. The sources added that the matter was being discussed at the State Department, with a decision on whether to proceed with the expulsion expected either late tonight or, more likely, on Wednesday.

The circumstances of the alleged espionage were not known. However, some sources said they believe there was a connection to arrests in Miami on Sept. 14 of 10 persons accused of collecting information on military installations and of attempting to infiltrate anti-Castro groups in southern Florida.

U.S. officials said at the time that the Miami arrests constituted the breakup of the largest alleged spy ring of agents in this country working for Cuban President Fidel Castro's communist government.

Cuba's U.N. diplomats work under the provisions of the world body's headquarters agreement with the United States. The agreement permits countries with which the United States does not maintain full diplomatic relations to have diplomats living in New York for the purposes of U.N. activities. But in the case of Cuba, severe restrictions are placed on its diplomats' movements and their ability to go outside of New York City.