The U.N. Security Council voted June 9 to place new sanctions on Iran that allows for searches of cargo to or from Iran and increases the number of individuals and companies subject to travel bans and an asset freeze.
U.S. President Barack Obama in early July signed unilateral sanctions on Iran that focus on the Iranian energy sector. The U.S. sanctions follow similar actions by the Australian and Canadian governments.
Karroubi said sanctions on Iran would backfire, bringing in profits for the Islamic Revolutionary Guard Corps, reports Radio Zamaneh, a Persian news service in the Netherlands.
Karroubi, a candidate in the volatile presidential election in Iran in 2009, said only the "weaker classes of society" would be hurt by economic sanctions.
Members of the IRGC were listed specifically in the sanctions passed by the Security Council.