Companies seeking U.S. government contracts must certify they do not knowingly engage in any significant transactions with Iran's Islamic Revolutionary Guard Corp (IRGC), according to  new rule adopted by several key agencies.

The IRGC is the major instrument of regime repression in Iran, and it also controls Iran’s nuclear program and much of the economy. The group was originally sanctioned by the United States in 2007 for its support of terrorism and proliferation activities. Recently, the group has been heavily involved in supporting the Assad regime in Syria and Hamas in Gaza.

The rule, adopted Dec. 7 by the Department of Defense (DOD), General Services Administration (GSA), and National Aeronautics and Space Administration (NASA), was required by the Iran Threat Reduction and Syria Human Rights Act (ITRSHRA) of 2012 and is part of a comprehensive policy aimed at the president and Congress’s goal of compelling Iran to abandon efforts to acquire a nuclear weapons capability.