Fidel Castro (search) accused President Bush on Friday of plotting with Miami exiles to kill him, and said he would die fighting if the United States ever invaded to oust him.

"I don't care how I die," Castro said at the end of a 5-hour speech that began Thursday night and continued into early Friday. "But rest assured, if they invade us, I'll die in combat."

The Cuban president didn't back up his accusations with details. He spoke at the close of a conference bringing together activists across the region who oppose the Free Trade Area of the Americas (search).

Castro has insisted over the past year that hardline Cuban exiles in Miami have been pressuring the Bush administration to invade the island — a charge U.S. officials deny.

Castro also has increasingly referred to his own mortality in recent years, promising to remain in power until his last breath.

"We know that Mr. Bush has committed himself to the mafia ... to assassinate me," the Cuban president said, using the term commonly employed here to describe anti-Castro Cuban Americans. "I said it once before and today I'll say it clearer: I accuse him!"

Castro has accused past U.S. administrations of seeking to assassinate him, and during his early years in power there were numerous documented cases of U.S.-sponsored attempts on his life.

The assassination of foreign leaders as U.S. policy was later banned in 1976 by an executive order signed by then-President Gerald Ford and reinforced by Presidents Jimmy Carter and Ronald Reagan.

Castro also criticized the Bush administration's Commission for a Free Cuba (search) — a panel set up in October and headed by U.S. Secretary of State Colin Powell.

When the United States announced creation of the commission, Powell suggested that the goal is not to ease Castro out but to plan a strategy for Cuba once the 77-year-old leader is no longer in power.

Earlier in his speech, Castro called on the more than 1,000 activists from across the Americas gathered here to work against the U.S.-backed free trade pact, which he said will only further impoverish their nations.

The Bush administration has progressively hardened its policies toward the island. Cuban authorities charge the strategy is aimed at wooing voters in Florida, home to most of the Cuban-American exiles living in the United States.

For more than four decades, the two countries have been without diplomatic ties and a U.S. trade embargo against the island makes most trade between the nations impossible, except for sales of farm products.