The UK is going to be "slapped in the face"... and "soon".
An Iranian cleric made that threat on Friday (July 12) in response to the seizure of an oil tanker by British Royal Marines last week.
Also on Friday, Iran demanded the ship's "immediate release" while warning of consequences.
And all this talk of retaliation seems to be backed by people on the streets of Tehran.
(SOUNDBITE) (Farsi) UNIDENTIFIED TEHRAN RESIDENT, SAYING: "If you want to know my opinion, I agree with it (blocking British tanker), because I think every action has a reaction." (SOUNDBITE) (Farsi) RESIDENT, MR RAEISI (FIRST NAME UNKNOWN), SAYING: "The measures that England has taken now requires us to show a reaction because our national interests are in danger and this is one of national interests." The tanker was seized off the coast of Gibraltar a week ago, suspected of violating sanctions by taking oil to Syria.
Iran denies this, and also denied the UK's claim on Thursday (July 11) that three Iranian vessels had tried to block a British-owned tanker in the Strait of Hormuz.
The tanker row comes amid escalating tensions between the U.S. and Iran and Iran's foreign ministry accused Britain of seizing the ship under U.S pressure.
Washington tightened sanctions on Iran from the start of May.
Tehran retaliated by decreasing its commitments to the 2015 nuclear deal signed with six major world powers.
The U.S has also blamed Iran for a series of attacks in the Strait of Hormuz - the world's most vital oil artery.
On Friday a spokeswoman for British Prime Minister Theresa May said discussions were ongoing between the U.S. and UK over increasing their military presence in the Gulf.