Dozens of Iranian professionals were refused to enter the United States earlier this month as they landed at several airports for a reunion of graduates of Sharif University of Technology in California after their visas were revoked without explanation, the report said.

"Scientific and academic relations and contacts are established phenomenon in the entire world," the Iranian organization said in a statement, urging scientific bodies around the world to protest against the U.S. authorities.

It also said the U.S. actions were "unjustifiable" and displayed "the retarded, Middle Ages style of behavior on the side of a government which alleges to be the main supporter of liberal democracy".

The Iranian professionals had obtained 15-day visitor visas to attend the fourth global alumni reunion of the Sharif University of Technology, a prestigious institution known as the "MIT of Iran", the report said.

However, only a handful of them successfully entered the United States, but the visas of the bulk of alumni from Iran had been revoked by the U.S. authorities under a 2002 national security law.