WASHINGTON, June 21 (Reuters) - Haiti's president said on Thursday that fighting drug trafficking and corruption in his impoverished Caribbean country was now the priority of his government.

Rene Preval said in an interview in Washington, D.C., that sustainable social and ...

... economic development was not possible unless both plagues were fought.

"Police officers, judges, customs and government officials are bought off by drug dealers and there will be no stability if traffickers are not defeated," Preval told Reuters during a meeting of Caribbean leaders in the U.S. capital.

"They will do anything to destabilize the government."

Haiti, the poorest country in the Americas, has suffered frequent waves of violent instability as it tried to build a democracy after decades of dictatorship.

Its first democratically elected leader, former Roman Catholic priest Jean-Bertrand Aristide, was ousted early in his first term in a military coup and then again during a later term through an armed rebellion in February 2004.

Preval's election last year revived hopes for peace and a U.N. peacekeeping force has in recent months had some success in tackling the street gangs that had taken control of the sprawling slums of the capital Port-au-Prince.

But Haiti remains a significant transshipment route for South American cocaine and its police and courts are notoriously corrupt, presenting challenges to efforts to build democratic institutions and economic conditions that would ease grinding poverty.

Preval and 14 other Caribbean leaders met with U.S. President George W. Bush on Wednesday to discuss trade, economic development and regional security.

Preval said when it was his turn to speak he addressed only the problem of drug trafficking.

"Because if this problem is not solved, there is no point in talking about a strong state, about investments, progress and stability," said Preval.

Preval, who recently submitted to parliament a bill that would force government officials and their close dependents to declare their assets every year, said corruption was a major threat to development.

"...If we allow smugglers and other corrupt officials to go unpunished, honest investors won't come to do business in our country," he said.

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