The State Department said yesterday it has ordered two Cuban diplomats at the United Nations expelled "expeditiously" on charges of violating U.S. statutes by buying and trying to purchase high technology electronics equipment.

Spokesman Dean Fischer, at the department's daily news briefing, said the U.S. mission to the United Nations on Monday "informed the Cuban mission to the United Nations that we have decided to expel two members of the Cuban mission and that they must depart the United States expeditiously."

The diplomats were identified as Mario Monzon Barata, a second secretary, and Jose Rodriguez Rodriguez, an attache.

They were charged with violating the Trading With the Enemy Act "by buying and trying to buy large quantities of high technology electronics equipment, much of it subject to strategic trade controls."

"Mr. Monzon had been involved in such violations for over a year," Fischer said in a statement. "Were it not for their diplomatic status, Mr. Monzon and Mr. Rodriguez would be subject to prosecution for violating and conspiring to violate the Trading With the Enemy Acct."

Fischer said the action was triggered July 1 when special agents of the U.S. Customs Service and the FBI in Florida seized "parts of a TV satellite monitoring system purchased by Mr. Monzon."

"Ongoing FBI counterintelligence investigations have determined that Mr. Monzon has been engaged in intelligence gathering," the statement said. He was said to be chief of the Center of the Cuban Director General of Intelligence in New York. Rodriguez was his secretary.

It was the first expulsion of a Cuban diplomat since the first secretary of the Cuban interests section in Washington was declared persona non grata Feb. 11, 1981, on charges he was an agent engaged in intelligence activities.