WASHINGTON -- In another sign of an easing of policy toward Cuba, the Clinton administration has given preliminary approval to a Connecticut firm to stage the first U.S. trade show on the island in nearly 40 years, according to the company and U.S. officials.

PWN Exhibicon International obtained a Treasury Department license to travel to Cuba to arrange an exhibition of products from 100 to 200 U.S. health-care companies. PWN President Peter Nathan said he hoped to hold the trade show -- featuring everything from X-ray equipment to operating tables and medicines -- within the next year.

Nathan said potential exhibitors include Fortune 500 companies, and he added that at least 100 American firms already have expressed interest in participating.

``There is a market there,'' he said. ``There's potentially a very large market. Some of them might be able to develop a relationship before any [U.S.-Cuban] relations change.'' Others, he said, ``want to get a foot in the door and know they will be in the forefront when relations change.''

Michael Ranneberger, director of the State Department's office of Cuban affairs, said the U.S. green light merely permits Nathan to ``explore'' preparations for the show. ``The fact that we've approved this travel license does not ensure that there will be approval for this exhibition,'' he said.

State Department spokesman James Foley confirmed that PWN Exhibicon received U.S. authorization on Oct. 23 of last year. The administration had rejected an earlier request on grounds that it would promote overall trade between the nations, U.S. officials said.

On Monday, U.S. officials insisted the approval did not reflect a change in policy, adding that the administration has authorized eight U.S. companies since 1992 to individually promote their health-care products in Cuba.

Washington cut off diplomatic relations with Havana in 1961 and imposed a trade embargo the following year. John Kavulich, president of the U.S.-Cuba Trade and Economic Council in New York, said the PWN event would be the first U.S. trade show since October 1959, when the American Association of Travel Agents convened in Havana.

Kavulich, who advises corporate clients interested in Cuba, called the administration's green light for a U.S. trade show ``the most significant change in U.S. commercial policy toward Cuba in almost 40 years.''

Individual participants in the show each would require a separate Treasury license, as would any sales conducted in the island. Under the 1992 Cuban Democracy Act, U.S. health-care companies may sell medicine or medical equipment in Cuba provided they can provide independent confirmation that the product is not used for resale or torture.

Prodded by Pope John Paul II, President Clinton last month ordered the Treasury Department to streamline procedures for allowing U.S. firms to sell medicine and health products to Cuba. The President also said he would once again allow direct flights and cash transfers to the island.

South Florida Republican Reps. Ileana Ros-Lehtinen and Lincoln Diaz-Balart, as well as Rep. Bob Menendez, D-N.J., have been among those criticizing the administration for a softening in U.S. policy. The Senate is expected to hold a hearing later this month on legislation to lift all restrictions on food and medical sales to Cuba.

``I think this is outrageous,'' Menendez said of the trade show. ``This is going to generate hundreds of thousands of dollars for the Castro regime. If the administration continues down this line of actions, their protests that this is not a policy change will ring hollow.''

Nathan, of PWN, said he has held trade shows for more than 40 years, including in the Soviet Union and China. Asked if he is an anti-embargo activist, Nathan replied: ``Only in the sense I believe that economics, rather than politics, determines how the world works.''

Luis Fernandez, a spokesman for the Cuban Interests Section in Washington, said he could not confirm whether the trade show had been approved by Havana.

``If this is correct, and it is a definitive step toward lifting the U.S. blockade, we'll give it the warmest welcome,'' Fernandez said.