US sanctions against top Iranian officials represent the "permanent closure" of the path to diplomacy with Washington, Irans foreign ministry said on Tuesday. "Imposing fruitless sanctions against Irans supreme leader (Ali Khamenei) and the commander of Irans diplomacy (Foreign Minister Mohammad Javad Zarif) is the permanent closure of the path to diplomacy with the frustrated US administration," ministry spokesman Abbas Mousavi said in a tweet. US President Donald Trump enacted new sanctions Monday targeting Khamenei. US officials also say they plan sanctions against Zarif. This comes amid heightened tensions between Tehran and Washington mainly after Iran last week shot down a US military surveillance drone. Iran says the drone was flying over southern Iran. Washington says it was downed in international airspace over the Strait of Hormuz in the Gulf. Trump said that the sanctions were in part a response to the shooting down of the drone, but would have happened anyway.