PHILADELPHIA — The FBI's counterterrorism agents lack the language skills and cultural understanding needed to succeed, an agency whistle-blower charged Saturday.

Bassem Youssef, a decorated FBI supervisor who was born in Egypt and speaks fluent Arabic, also said jealousy, discrimination and flawed directives hinder the FBI's attempts to fight terrorism.

"The FBI has publicly stated that expertise in working counterterrorism matters, and cultural understanding of the Middle East and the radical Islamic groups, as well as the language, are not necessary to run the counterterrorism division," said Youssef, speaking publicly for the first time on the subject Saturday at an American Library Association meeting.

Youssef, 49, the highest ranking Arab-American agent, has a discrimination lawsuit pending against the bureau. He has also raised concerns about the FBI's alleged misuse of warrantless searches.

Youssef canceled plans to deliver prepared remarks, after what his lawyer called FBI censorship and threats of disciplinary action, and instead answered questions from the audience.

FBI spokesman Richard Kolko said speeches are reviewed to protect employees and classified information, but that the agency respects its employees' First Amendment rights.

Youssef's lawsuit, filed in 2004, alleges that he was passed over for several promotions after the Sept. 11, 2001, attacks despite his relevant skills and experience, including a stint in Saudi Arabia when he said he came to know Osama bin Laden's brother.

The FBI denies discriminating against him and says it now has 46 agents and 285 language analysts who speak at least conversational Arabic.

"We have enough language qualified personnel to do our job, but that doesn't mean we don't want more and we are continuing our recruiting efforts in this area," Kolko said in a statement Saturday.

Youssef earned a distinguished service medal from the CIA in 1994 after infiltrating the Islamic group led by blind Sheik Omar Abdel Rahman, the mastermind of the 1993 World Trade Center bombing.

In recent years, he has run an FBI communications analysis unit within the counterterrorism division.

In July 2006, the Justice Department's Office of Professional Responsibility concluded that the FBI had retaliated against Youssef because of disclosures he made to the agency's director and a member of Congress.

No trial date has been set for his discrimination lawsuit.