HAVANA - Former Cuban leader Fidel Castro said on Sunday the U.S. trade embargo against Cuba must go, but he was mum on his brother Raul Castro's recent offer to talk with Washington about everything, including political prisoners and human rights.

Castro's comments in his latest column in Cuba's state-run media were his first about the just-completed Summit of the Americas in Trinidad and Tobago. Latin American leaders there pushed U.S. President Barack Obama to end the Cold War trade ban imposed against Cuba in 1962.

Castro praised Obama for being very intelligent, but said he was abrupt and evasive when he answered questions about the embargo in a closing news conference on Sunday.

I want to remind him of a basic ethical principal related to Cuba: any injustice, any crime in whatever time has no excuse to go on. The cruel blockade (embargo) against the Cuban people costs lives, costs suffering, he said.

Before the summit that began on Friday, Obama put small holes in the embargo by granting Cuban-Americans the right to travel freely to Cuba and send unlimited money to their relatives on the communist-ruled island.

Obama said he hoped Cuba would signal its willingness to move ahead by releasing political prisoners and cutting the amount it charges to change U.S. dollars into Cuban convertible pesos.

President Raul Castro said on Thursday that Cuba was willing to hold talks with the United States in which even sensitive topics for Cuba -- human rights, political prisoners and freedom of the press -- could be on the table.

The test for all of us is not simply words, but deeds, Obama said on Sunday. Obama has said he wants to recast the U.S.-Cuba relationship but would use the embargo as leverage for Cuban reforms. [nN19374252]

Raul Castro's words were taken by the administration as a signal Cuba wants to move toward better relations, but Fidel Castro said nothing about the comments in his column.

He has written previously that Cuba is not afraid to have a dialogue with the United States.

Castro quoted at length from a summit speech by his ally, Nicaraguan President Daniel Ortega, who spoke of a long history of grievances against the United States and said he once told former U.S. President Jimmy Carter, Nicaragua does not have to change, the ones that have to change are you (Americans).

Nicaragua has never thrown a rock against the North American nation, Nicaragua has never imposed governments on the United States. You are the ones who have to change, Ortega said.

Barack obama Cuba