The statement comes several hours after the WSJ reports about the White House's plans to designate Iran's Revolutionary Guard Corps (IRGC) a foreign terrorist organisation (FTO) on 8 April. If taken, this move would be the first time the US has officially blacklisted another county's military as terrorists.
"If the Revolutionary Guards are placed on America's list of terrorist groups, we will put that country's military on the terror blacklist next to Daesh*", Heshmatollah Falahatpisheh, the head of parliament's national security committee, said on Twitter.
Both Tehran and Washington have previously accused each other of supporting terrorism and called each other's actions "terroristic" literally or figuratively.
The decision to designate a group a terrorist organisation is done by the secretary of state, US attorney general and the secretary of the Treasury if the Congress doesn't block their decision. The group claimed to be a terrorist organisation, however, may request a US appeals court to review the designation.
At the moment the IRGC has already been sanctioned by Washington, as the Department of Treasury imposed sanctions on it in October 2017 under a 9/11-era executive order issued during the George W. Bush administration.
* Daesh (ISIL/ISIS/IS/Islamic State) is a terrorist organisation banned in Russia