Iran and the United States were at odds on Monday over the European Union's decision to label the military wing of Hezbollah as a terrorist group.
Iran backs Hezbollah financially and with weapons and training. The Iranian government called the move "strange" and "uncalculated."
The White House applauded the EU decision and said it sends a clear message that there are consequences for terror attacks.
Israel has called on the European Union to blacklist Hezbollah for years, but the EU refused because Hezbollah is part of the Lebanese government.
But the issue smacked the EU in the face last summer when Hezbollah was accused of terror activities in Cyprus and bombing a bus full of Israeli tourists in Bulgaria, killing six.
Hezbollah has long been involved in terror attacks. It is believed the group carried out deadly bombings in 1983 of the U.S. embassy and U.S. and French military bases in Beirut, killing more than 350 people, 250 of them Americans.
It carried out massive attacks on Israeli sites in Argentina in the 1990s. Currently the group has some 50,000 missiles pointed at Israel.