Former Cuban President Fidel Castro has condemned "Israel's" attack on the Gaza-bound Freedom Flotilla, calling it a "Nazi fascist fury."

The Zionist occupation's commandos who boarded the ships on the Monday dawn attack in international waters fired "frenetically" at the aid workers, Castro said in an article on Wednesday.

The Cuban icon and former President Fidel Castro, 83, writes regular columns for Cuban media commenting on world events.

Castro also said it is unlikely that US President Barack Obama will be able to serve another term in office if the United States does not launch a nuclear attack on Iran.

"Is it possible," Castro wondered, for Obama to be re-elected "without the Pentagon of... "Israel"... use nuclear weapons against Iran?"

However, the report did not provide more details about the logic behind Castro's comment.