CLINTON CONSIDERS RESPONSE TO CUBA\U.S. calls meeting of Security Council.

Byline: Tim Weiner The New York Times

The United States called an emergency meeting of the U.N. Security Council on Sunday as President Clinton weighed retaliating against Cuba for downing two civilian aircraft carrying anti-Castro Cuban-Americans.

Secretary of State Warren Christopher said two Cuban MiG fighter jets failed to warn off the American pilots before blowing their Cessna aircraft out of the sky with missiles on Saturday. He said such a failure violated international law and "the norms of civilized behavior."

But U.S. intelligence officials said that at least one of the American aircraft - the lead plane, which returned safely to Florida - and perhaps all three had violated Cuban airspace. They also said the air traffic control tower in Havana had warned the pilots that they were in danger.

In addition to convening the emergency Security Council session Sunday night, Clinton was trying to decide if and how the United States would react on its own. With a tight U.S. economic embargo of Cuba already in place, Clinton has few ways to single-handedly make life harder for Cuba and its leader, Fidel Castro.

Clinton is trying nonetheless to fashion a political and diplomatic response that will satisfy Cuban-Americans opposed to Castro, the only Communist leader in the Western hemisphere, without unduly punishing Cubans on the island who are seeking political changes.

The most powerful anti-Castro activist in Florida, Jorge Mas Canosa, said the deaths of four Americans in the incident offered Clinton "a golden opportunity" to win votes among Cuban-American conservatives by imposing the harshest possible sanctions, including severing all U.S. diplomatic, economic and political ties to Cuba.

He said the president should halt telephone service, ban charter flights, stop wire transfers of millions of dollars from Cuban-Americans sending money to relatives, close the U.S. interests section in Havana and withdraw all U.S. diplomats from the island.

But imposing those sanctions would be "shooting ourselves in the foot," Wayne Smith, who was the chief U.S. diplomat in Cuba as head of the interests section in Havana from 1979 to 1982, said in a telephone interview here.

"That would be absolutely absurd," Smith said. "The administration has been talking about the need to expand contacts, reach out to the Cuban people, let light into the island. Closing our interests section, cutting off communication - that goes against what we want to do, and what all the dissidents that I know on the island and all the religious leaders want to do, which is letting in more light."

Smith said the U.S. sanctions against Cuba were already so severe that there was little left to do except go to the United Nations.

The attack Saturday came after months of a dangerous cat-and-mouse game played between the Cuban air force and the anti-Castro group, Brothers to the Rescue, made up largely of Cuban exiles.

The group, which is based in Miami, had flown over Cuba at least twice before. Last month it dropped thousands of leaflets on Havana, urging Cubans to "Fight for your rights" and proclaiming, "Your problem is mine."

Each time, the Cuban government protested the action as a violation of international and U.S. law. It put Washington on notice that it would take "all necessary measures" to halt the planes, including shooting them down.

On Saturday, the three planes from the group left an airfield in Opa-Locka, Fla., shortly before 2 p.m. The group's founder, Jose Basulto, was flying the lead plane.

The pilots' stated mission was to look for Cuban refugees floating toward the United States. The flight plan they filed with the FAA called for a five-hour trip to the edge of the 24th parallel, a line on the map north of the 12-mile perimeter of Cuba's legal airspace.

FAA officials said the flight plan was transmitted electronically to air-traffic controllers in Havana.

Under international law, territorial airspace and waters end 12 miles from land. But nations can declare "air defense identification zones" and warn aircraft of danger beyond them. Cuba has legally declared the 24th parallel, which ranges from 40 to 60 miles from its jagged northern coast, as an air defense zone.

At 2:57 p.m., according to a chronology prepared by U.S. intelligence officials, one of the planes contacted Havana's civilian air-traffic controllers. The pilot said the planes would be headed south of the 24th parallel, in violation of their flight plan.

The Cuban controller warned the planes of the danger of crossing that line. The pilots said they were well aware of the risks, but were flying south over the line anyway, the intelligence officials said.

At 3:01 p.m., the planes crossed the 24th parallel. Eight minutes later, two Cuban fighter jets, a MiG-23 and a MiG-29, took off in pursuit. By 3:22 p.m., Basulto's plane was about 3.5 miles deep into Cuban airspace.

At 3:24 p.m., the MiG-29 pilot locked its radar on the second plane and requested and received permission from his military commanders to shoot it down.

Eyewitnesses on a cruise ship below the confrontation said the Cessna suddenly exploded. U.S. officials said the plane was downed about 5.75 miles north of Cuban airspace; Cuban officials said the shooting took place over Cuba's territorial waters.

At 3:31 p.m., the MiG-29 pilot requested and received permission to destroy the third Cessna and did. Again, U.S. officials said it went down in international waters; the Cubans disagree. Basulto, meanwhile, was headed back to Florida.