Iran's ambassador to the UK has been summoned to the Foreign Office following an attack on an oil tanker in which a Briton was killed.
The UK has said it is highly likely that Iran was behind the drone strike on the MV Mercer Street off the coast of Oman.
Middle East minister James Cleverly told Iranian diplomat Mohsen Baharvand that Tehran must "immediately cease actions that risk international peace and security".
The strike on the vessel last Thursday night was the first known fatal attack after years of assaults on commercial shipping in the region linked to tensions between Israel and Iran.
British maritime security firm Ambrey said the attack, which saw a hole blasted through the vessel's bridge, killed one of its employees on board.
The Mercer Street is managed by London-based Zodiac Maritime, part of Israeli billionaire Eyal Ofer's Zodiac Group.
The Foreign Office said the drone assault followed similar attacks on three other Israeli-linked ships in the region since February.
A Foreign Office spokesman said: "The Iranian ambassador to the UK, Mohsen Baharvand, was summoned today to the Foreign, Commonwealth & Development Office by the minister for the Middle East, James Cleverly, in response to the unlawful attack committed on MV Mercer Street on 29 July.
"Minister Cleverly reiterated that Iran must immediately cease actions that risk international peace and security, and reinforced that vessels must be allowed to navigate freely in accordance with international law."
Foreign Secretary Dominic Raab has promised to work with allies on a "concerted response" to Iran following the attack, which also killed a Romanian.
US Secretary of State Antony Blinken said he is confident that Iran carried out the attack using explosive drones – "a lethal capability it is increasingly employing throughout the region".
Tehran has denied responsibility, accusing Israel of making baseless accusations against Iran.