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By Jeff Mason and Matt Spetalnick
HAVANA, March 22 (Reuters) - U.S. President Barack Obama delivered an impassioned appeal for political liberties in Cuba, including freedom of expression and religion, as he spoke directly to the Cuban people on Tuesday in a historic speech broadcast throughout the Communist-ruled island.
Speaking at Havana's Grand Theater with Cuban President Raul Castro in attendance in what White House officials touted as a crowning moment of Obama's visit, Obama extended a "hand of friendship." He declared that he had come to Havana to "bury the last remnant" of the Cold War in the Americas.
But he also pressed for economic and political reforms, speaking in a one-party state where little dissent is tolerated.
"Voters should be able to chose their governments in free and democratic elections," he said.
"Not everybody agrees with me on this, not everybody agrees with the American people on this but I believe those human rights are universal. I believe they're the rights of the American people, the Cuban people and people around the world," Obama said.
His address marked the final day of his trip, the first by a U.S. president to Cuba in 88 years. His presence in Havana was the culmination of a diplomatic opening that he and Castro announced in December 2014, ending decades of estrangement between Washington and Havana that began soon after Cuba's 1959 revolution.
Obama drew strong applause from the audience when he reiterated his call for an end to the longstanding U.S. economic embargo against Cuba, which only the U.S. Congress can lift.
Obama, who abandoned a longtime U.S. policy of trying to isolate Cuba, wants to make his shift irreversible by the time he leaves office in January and secure it as a piece of his foreign policy legacy.
But major obstacles remain to full normalization of ties, most notably the continuing U.S. embargo and differences over human rights.
The Republican-controlled Congress has so far rejected the Democratic president's call for a lifting of the embargo, although Obama has used his executive powers to ease some trade and travel restrictions on the island.
The president's critics at home have called his visit a premature reward to the Castro government. U.S. House of Representatives Speaker Paul Ryan, a Republican, said on Tuesday the trip legitimizes what he called Castro's "tyrannical dictatorship."
With his words carried live by Cuba's state-run media, Obama sought to persuade ordinary Cubans that his new policy, including easing of trade and travel restrictions, was focused primarily on helping them to improve their lives.
Standing at a lectern flanked by U.S. and Cuban flags, Obama laid out a hopeful vision of future U.S.-Cuban relations and told Cubans "it's up to you" to take steps to change the country.
On Monday he sparred with Castro at a news conference where both leaders aired some of the old grievances between their countries, even as they sought to advance the diplomatic thaw.
Castro, an army general who took over as president from his ailing brother, Fidel Castro, in 2008, was at the theater to greet Obama on arrival and sat in the audience for the speech. At the end of the speech, the Cuban leader lightly applauded from the balcony, then waved to the crowd.
Obama's words at times were as much aimed at the Castro government as at the Cuban people, especially when he urged political freedoms and faster economic reforms to take advantage of the U.S. opening to the island.
"I believe citizens should be free to speak their minds without fear, to organize and to criticize their government and protest peacefully," said Obama.
Obama's administration is seeking to bridge the ideological divide by galvanizing the support of the Cuban public to help him pressure their government for reforms that so far have been slow to come.
However, the Cuban government has made plain that it does not see the detente as a path to political changes on the island.
After the speech, Obama met privately with about a dozen Cuban dissidents at the U.S. Embassy. He noted that some of them had been detained and commended them for their courage. Among the participants was Berta Soler, leader of Ladies in White, a protest group.
Obama and his aides say the future pace of rapprochement depends heavily on whether the Cuban government is ready to start loosening its grip on its Soviet-style economy and its heavily controlled society.
Obama's much-anticipated address marked the first time a sitting U.S. president's speech was broadcast to the Cuban people while on Cuban soil - though speeches by visiting popes have been carried live by state media.
Jimmy Carter, traveling to Cuba in 2002 as the first former U.S. president to visit since the revolution, called for political freedoms in a speech broadcast on live television.
Additional reporting by Dan Trotta and Frank Jack Daniel; Editing by Frances Kerry