HAVANA - President Barack Obama opened the door on Thursday to more changes in U.S.-Cuba policy, but based them on Cuban reciprocation that analysts said may be difficult to get.

He told CNN that after lifting restrictions on Cuban American travel to the communist-led island this week, he was looking for some signal that there are going to be changes in how Cuba operates with regard to such things as political prisoners and freedom of speech.

While he stopped in Mexico on his way to the Summit of the Americas starting on Friday in Trinidad and Tobago, Secretary of State Hillary Clinton told reporters in Haiti that we stand ready to discuss with Cuba additional steps that could be taken.

We would like to see Cuba open up its society, release political prisoners, open up to outside opinion and media and have the kind of society that we all know would improve the opportunities for the Cuban people and for their nation, she said.

There was no immediate response from Cuba, where leaders have spoken well of Obama and expressed openness to dialogue, but eschewed the idea of U.S.-mandated pre-conditions on what they consider domestic issues.

Cuba is said to have about 200 political prisoners, whom it considers mercenaries for the United States.

President Raul Castro has said any U.S. talks must be held without even the slightest shadow over our sovereignty.

We are not in any hurry, we are not desperate, he said in a January interview on Cuban television. We will not talk with the stick and the carrot. That time is over.

What that means, said Washington attorney Robert Muse, a specialist in Cuban issues, is that they will never accept conditionality -- the idea that if you do this, you'll get some ill-defined benefit down the road.

You can put the ball in their court, but the Cubans will never swing at it. They just won't play, he said.

'CONFIDENCE-BUILDING MEASURES'

The U.S. leaders' comments followed a Monday announcement that Obama had granted Cuban Americans the right to travel freely to Cuba and removed limits on how much money they can send to family there.

He also eliminated restrictions for U.S. telecommunications companies, in theory opening the way for them to offer services to Cuba to promote what U.S. officials called a freer flow of information.

The moves reversed regulations put in place by the Bush administration and were the first by Obama to chip away at Cold War-era U.S. policy aimed at toppling the Cuban government, the cornerstone of which has been a trade embargo imposed since 1962.

He has said the United States should move toward normalizing relations with Cuba, but maintain the embargo for leverage on human rights and democracy.

Cuba expert Dan Erikson at the Inter-American Dialogue in Washington said Obama's changes are laudable, but he may be reducing the likelihood of a positive Cuban response by framing the moves as a way to export democracy and weaken control of the Cuban state.

While Obama may believe he is offering an olive branch, the accompanying rhetoric could make the Castro brothers interpret it as a hostile act unless the U.S. simultaneously launches new confidence-building measures, he said.

Former leader Fidel Castro wrote in columns published on Tuesday in state-run media that the lifting of travel restrictions was positive, but minimal and said many other changes were needed.

But he also complained that not one word was said by the White House about the embargo and ended with a defiant flourish.

Cuba has resisted and will resist. It will never extend its hands to beg. It will go forward with its head high, wrote the reclusive 82-year-old who ruled Cuba for 49 years after taking power in a 1959 revolution. He maintains a high profile through his writing.

Cuba expert Paolo Spadoni said Cuban leaders might make minor concessions to the United States, but nothing major because they place the blame for 50 years of hostilities squarely on the Americans.

Their position is you have a policy against us, it's not our policy so we don't really have to do anything to lift it -- you should do it,' said Spadoni, currently on fellowship at Tulane University's Center of Inter-American Policy and Research in New Orleans.

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