HAVANA (AP) - Cuban scientists at the Nonaligned Movement summit on Wednesday denied any effort to develop biological or chemical weapons, dismissing U.S. allegations that Cuba's biotechnology center doubles as an undercover weapons factory.

"We have no ties to anything related to biological weapons, it has nothing to do with what we focus on,'' said Luis Herrera Martinez, director of the Center for Genetic Engineering and Biotechnology.

For years, U.S. officials have raised suspicions about the center. John Bolton, now the U.S. ambassador to the United Nations, alleged in 2002 the communist state had "at least a limited offensive biological warfare.''

But Herrera said his scientists would have to be "stupid'' to develop biological or chemical weapons.

"We don't have the money to be dedicated to that, and and we are not interested,'' Herrera said.

"We would have to be stupid to be doing what these accusations imply, we wouldn't even be able to do anything like that. It doesn't make any sense, it does not go with our work ethic or interests.''

Herrera said the center makes 91 products, including 33 drugs developed to fight infectious diseases, and that Cuba has 12,000 registered scientists, impressive for a relatively poor nation, reflecting the importance the Cuban government places on medicine and science.