"If the IRGC is placed on the US list of terrorist groups, we will put the country's military personnel on the terrorist blacklist alongside Daesh," Chairman of the Iranian Parliament's Committee on National Security and Foreign Policy Heshmatollah Falahatpisheh tweeted on Saturday, Press TV reported.
The warning came after three American officials told Reuters that the US is expected to designate the IRGC as a foreign terrorist organization.
The decision, the officials said, will be announced by the US State Department, perhaps as early as Monday.
The US has already blacklisted dozens of entities and individuals affiliated with the IRGC, but not the group as a whole.
The IRGC was formed at the order of Imam Khomeini, the late founder of the Islamic Republic, shortly after the 1979 revolution in a bid to protect the revolution and battle insecurity in the country.
The group, which is a branch of Iran’s Armed Forces, played a major role in defending the country during the 1980-1988 imposed war with Iraq.
Over the past four decades, it has successfully foiled conspiracies hatched by the enemy against the Islamic Republic.
The IRGC, which has roughly 125,000 military personnel and enjoys growing public support, is also actively cooperating in construction, infrastructure and relief projects.