CARTAGENA, Colombia -- Leaders of Latin America, Spain and Portugal have agreed to seek an end to the 30-year-old U.S. trade embargo against Communist Cuba. At the end of the fourth-annual Ibero-American summit on Wednesday, more than 20 heads of state and government approved a declaration that included their most critical reference ever to U.S. economic measures against Cuba. Many of the leaders also pressured Cuban President Fidel Castro to implement democratic reforms in his country, although that was not part of the declaration. In a news conference, however, President Carlos Saul Menem of Argentina linked the two issues. "We want Cuba to return to democracy, so we are going to pressure strongly for the United States to withdraw those measures," Menem said. A Latin American diplomat predicted that the region's leaders will ask President Bill Clinton to lift the embargo when they meet at a summit of Western Hemisphere nations scheduled for December in Miami. "They are going to tell Mr. Clinton: more trade, more interchange, and you are going to see things change in Cuba," the diplomat said. None of the leaders defended Cuba's communist system. "We all want Cuba to change economically and politically," said Colombian President Cesar Gaviria. The summit included discussion of restoring Cuba to the Organization of American States and efforts to create a Western Hemisphere free-trade zone. Menem of Argentina said that without democratic reforms, Cuba would be excluded from such a zone. "It is the decisive step that Cuba must take -- return to democracy -- to be integrated completely with the other countries of Latin America," he said.