Cuban-American leaders in Congress are expressing outrage that the governor of Nebraska, David Heineman, will lead a trade delegation to Cuba in the immediate wake of crackdowns on dissidents and as leaders of the island’s pro-democracy movement encounter greater repression from Cuba’s communist dictator, Fidel Castro.

They are urging the governor, who is seeking to establish a long-term trade relationship with the Cuban government, to mitigate the effects of his trip by visiting with dissidents, advocating the release of political prisoners, and urging free elections on the island during his stay in Cuba.

Mr. Heineman, a Republican who took office in January, is leading the first trade mission of his governorship to Havana from August 13 to 17. The purpose of the trip is to negotiate the purchase of Nebraska-grown dry beans, one of the state’s largest exports, by the Cuban government. Mr. Heineman will lead a 10-member delegation – which includes representatives of Nebraska’s agricultural lobby – in meetings with the Cubans, the Nebraska official in charge of organizing the trade mission, Stanley Garbacz, said yesterday.

Mr. Garbacz said he had led several trade missions during his 25 years with the Nebraska Department of Agriculture, and that, “next to the Chinese,” the Cubans “were the most difficult to try to pin down in terms of what we’re going to do while we’re there.” Mr. Garbacz said he did not know whether the delegation would be meeting with Mr. Castro but said that they would meet with representatives of the Cuban government entity responsible for the importation of agricultural commodities, Alimport, and would probably speak to Mr. Castro’s ministers of foreign trade and agriculture.

In addition to securing a purchase of Nebraska dry beans, Mr. Garbacz said, the state’s delegation would be laying the foundation for a long-term relationship with the regime, particularly over other Nebraska exports – such as beef, pork, corn, and wheat.

Some Cuban-American leaders in Congress, however, said yesterday that the trade mission would succeed only in “sending the appalling signal that the cash of tyrants is more important than the lives of pro-democracy leaders.”

Rep. Lincoln Diaz-Balart, Rep. Mario Diaz-Balart, and Rep. Ileana Ros-Lehtinen, all Republicans of Florida, sent a letter yesterday to Mr. Heineman denouncing his willingness to visit Cuba and trade with Mr. Castro’s regime in the wake of recent crackdowns on the island’s dissident movement.

“Your decision to travel to totalitarian Cuba at this time demonstrates a profound insensitivity toward the suffering of the Cuban people and to the fact that Cuba is one of only six remaining state sponsors of terrorism in the world today,” the representatives’ letter stated.

On July 22, the Castro regime rounded up and jailed more than 30 dissidents as they prepared a nonviolent demonstration outside the French Embassy in Havana to protest France’s exclusion of dissidents from its Bastille Day celebration. Some of the pro-democracy activists arrested that day remain jailed, including Rene Gomez Manzano, one of the leaders of the May 20 meeting of the Assembly to Promote Civil Society in Cuba.

The congressmen called on Mr. Heineman to meet with the other leaders of the Assembly, Martha Beatriz Roque Cabello and Felix Bonne Carcasses, and with Cuban political prisoners, including Mr. Gomez and Oscar Elias Biscet. Dr. Biscet is a leading dissident imprisoned since March 2003, when Mr. Castro rounded up 75 independent academics, journalists, librarians, and other democracy activists.

A spokesman for Mr. Heineman, Aaron Sanderford, responded yesterday: “The governor deeply regrets the attempted political polarization of a trip that is narrowly focused on agricultural trade.”

“He is hopeful,” Mr. Sanderford said, “that the Cuban people will recognize the quality and benefits of the products our farmers and ranchers provide. He has expressed repeatedly that he intends to work within the framework of established law and that he will not engage in the politics of the day.”

Mr. Sanderford said Mr. Heineman would not be meeting with dissidents, advocating the release of political prisoners, or urging free elections during his trip. The governor’s office has also said that the sale of some agricultural and humanitarian goods to the Cuban people is legal despite the embargo, and said the trip would be conducted completely within the bounds of American law.

The congressmen and scholars of Cuba said yesterday, however, that products sold to the government of Cuba rarely reach the Cuban people. “It is important for you to know that in totalitarian Cuba, all commercial transactions take place through a dictatorship which oppresses its people. Castro directly controls – and exploits – the distribution of all goods and services in Cuba,” they wrote.

The director of the Washington-based Center for a Free Cuba, Frank Calzon, said yesterday that while Mr. Heineman probably felt he was simply securing business for his state, he was likely an unwitting aide to Mr. Castro in his efforts to get America to lift its trade embargo on Cuba.

“As far as Castro’s concerned, he’s not buying agricultural goods,” Mr. Calzon said. “He’s purchasing a lobby.”

Lincoln Diaz-Balart, meanwhile, said that beyond the economics, Mr. Heineman’s mission was offensive on principle. “It’s like saying politics is not part of a trip to Hitler’s Germany in the 1930s,” Mr. Diaz-Balart said yesterday. “It’s not a question of politics – it’s a question of elemental human decency.”

Mr. Diaz-Balart’s criticisms came as new reports of efforts by Mr. Castro to thwart the island’s increasingly active pro-democracy movement emerged from Havana yesterday – and as Ms. Roque issued stern criticisms of European accommodation of Mr. Castro.

According to the Miami-based support center for the Assembly to Promote Civil Society in Cuba, a follow-up meeting to the May 20 gathering was violently interrupted yesterday as agents of Mr. Castro’s regime harassed pro-democracy activists in their homes before the meeting, and then formed a double human chain outside the meeting, preventing the democracy activists from gathering.

Last week, the European Commission canceled an event with dissidents and the families of prisoners scheduled to take place at E.U.’s Havana offices following protests by agents of the Castro regime. The European decision to break off contact with dissidents as a response irked Ms. Roque, who said in a statement yesterday that the recent increases in harassment of the Cuban opposition were evidence that the Castro regime feels emboldened by the acquiescence of the European Union.

In addition to last Friday’s decision by the European Commission, and the French Embassy’s decision to exclude dissidents from its celebrations in July, the European Union determined in June that it would grant Mr. Castro another year of “constructive dialogue” before reconsidering whether to impose diplomatic sanctions on the regime. The decision was reached despite the E.U.’s acknowledging that Mr. Castro had not, during the previous six months of “constructive dialogue” and reprieve, made any steps toward freeing political prisoners or opening Cuban society.