castro_obama.jpgHAVANA (AP) _ Raul Castro gave the strongest signal yet that his government's would-be honeymoon with the Obama administration is over, delivering a harshly worded speech Sunday charging that the White House endorses efforts to topple the island's communist system.

Offering Cuba's first public acknowledgment of the arrest of an American contractor, Castro said the case shows “the United States won't quit trying to destroy the revolution and bring a change to our economic and social regime.''

“In the last few weeks we have witnessed the stepping up of the new administration's efforts in this area,'' he told parliament. “They are giving new breath to open and undercover subversion against Cuba.''

Castro gave no specific charges against the U.S. citizen, but said he was “working to illegally distribute sophisticated methods of satellite communication to members of the 'civil society' which they hope to form against our people.''

The U.S. State Department previously confirmed the Dec. 5 arrest but has not released the name of the person involved, citing privacy issues. American diplomats in Havana have asked for but not received access to the detainee, who was working for a Maryland-based development organization.

Castro said this year's U.S. federal budget allocated “almost $55 million to support a supposed democracy, the defense of human rights and aggression by radio and television against Cuba'' _ a reference to Radio and TV Marti, which broadcast from U.S. territory to Cuba to provide an alternative to state-run media.

Castro again repeated his offer to sit down with President Barack Obama and discuss relations that have been ice cold for nearly a half century, since an armed revolution put his brother Fidel in power on New Year's Day 1959.

But he strongly criticized the Obama administration, saying Washington has begun “exclaiming cynically that we have returned to Cold War and anti-American discourse.''

Better U.S.-Cuba relations seemed a real possibility as recently as the spring.

The White House eased restrictions on Cuban-Americans who want to travel and send money to this country, and Obama spoke of a possible new beginning with the island _ although others in his administration suggested they would like to see Cuba embrace small economic and democratic reforms.

Fidel Castro, who ceded power to his younger brother in February 2008, at first praised Obama, even supporting his winning of the Nobel Peace Prize. But the elder Castro wrote last week that Obama's “friendly smile and African-American face'' are hiding Washington's sinister intentions for Latin America.

Those words came after both sides blamed each other for the postponement of meetings in Havana scheduled for this month to discuss immigration issues.

In November, the State Department denounced an assault allegedly inflicted by plainclothes Cuban state security agents on the island's top dissident blogger, Yoani Sanchez. Obama later sent a lengthy message praising Sanchez and answering a series of questions from her.

Prominent American blacks recently denounced racism in Cuba, which is a touchy subject here, and the Cuban military conducted war games against a U.S. invasion, which authorities here still insist is a real possibility.

“If the American government really wants to advance relations with Cuba,'' Raul Castro said Sunday, “I recommend they leave behind the conditions of internal governance that they are trying to impose on us and that only Cubans can decide.''

Pictured above are Raul Castro, left, President Barack Obama, center, and Fidel Castro, right.