WASHINGTON (Reuters) - Talk of ending the United States’ 47-year old Cuban trade embargo was premature and won’t happen unless Havana alters its policies, President Barack Obama’s top economic advisor said on Sunday.

“That is way down the road, and it is going to depend on what Cuba does going forward,” White House Director of the National Economic Council Lawrence Summers told NBC’s “Meet the Press”, when asked under what circumstances Obama would lift the embargo.

“Cuba’s known what it needs to do for a very long time, and it is up to them in terms of their policies, their democratization, all the steps they can take,” Summers said.

Obama last week relaxed parts of the trade embargo, imposed by Washington following Fidel Castro’s 1959 revolution. The move drew conciliatory remarks from Cuban President Raul Castro and has raised hopes of rapprochement between the two nations.

Summers, a former treasury secretary during the Clinton administration, said that the possibility of trade with Cuba would be a good thing for the United States but would not be a decisive factor in driving the historic decision.

“This is an issue that is going to get decided on the basis of Cuba’s behavior. On the basis of the steps they choose to take, the steps they choose not to take in their policies in this hemisphere. It is about whether they really want to join the community of nations in Latin America or not,” he said.