Iran is warning the United States against designating its Revolutionary Guards as a terrorist organization, saying it would put the United States on the side of the Islamic State group.

Government spokesman Mohammad Bagher Nobakht told reporters Tuesday the guards are “the defender of the nation” and if the United States designates the military force a terror organization “it puts itself in the camp of terrorists.”

"Any country that wants to have such a position about the Guards will share this view with the Daesh terrorists," he said, using another name the Islamic State group.

U.S. media reports indicate President Donald Trump may designate the Guards as a terrorist organization as part of a larger strategy to increase pressure on Iran over its nuclear program.

Trump has repeatedly bashed a deal signed last year by Iran and leading world powers curbing Tehran's nuclear program in exchange for the lifting of sanctions. He must decide by Sunday whether to recertify the agreement, but is widely expected to declare Iran non-compliant with it, which would require Congress to make a decision on re-imposing sanctions.

Iranian Armed Forces spokesman Masoud Jazayeri told ISNA if Trump decides to designate the Guards as terrorists, Iran would “teach Americans a new lesson.”

"It seems the Trump administration only understands swear words, and needs some shocks to understand the new meaning of power in the world," Jazayeri said.