Dubai - Iran's President Hassan Rouhani said on Wednesday Britain would face "consequences" over the seizure of an Iranian oil tanker.
Iran has demanded the immediate release of the Grace 1, which British Royal Marines boarded off Gibraltar last week and seized on suspicion that it was breaking sanctions by taking oil to Syria.
"You (Britain) are the initiator of insecurity and you will realise the consequences later," Rouhani said after a cabinet meeting, in remarks carried by state television.
"Now you are so hopeless that, when one of your tankers wants to move in the region, you have to bring your frigates (to escort it) because you are scared. Then why do you commit such acts (seizure)? You should instead allow navigation to be safe," Rouhani said.
Rouhani also said Iran's decision to increase uranium enrichment would produce fuel for power plants and serve other peaceful aims, and that it was within the framework of Iran's 2015 nuclear deal with world powers.