Iran's Zarif tweets: U.S. treasury is nothing more than a "jail warden"

The U.S. Treasury is nothing more than a "jail warden", Iranian Foreign Minister Mohammad Javad Zarif tweeted on Thursday, a day after Washington imposed fresh sanctions designed to choke off the smuggling of Iranian oil.

"OFAC (Office of Foreign Assets Control of U.S. Treasury) is nothing more than a JAIL WARDEN: Ask for a reprieve (waiver), get thrown in solitary for the audacity. Ask again and you might end up in the gallows," Zarif wrote on his Twitter account.