“Certainly if the hostile actions of some European countries continue, the export of oil to these countries will be cut,” Deputy Oil Minister Ahmad Qalebani said.

Iran halted oil exports to France and the UK on Sunday.

National Iranian Oil Company (NIOC) earlier sent letters to a number of European oil refining concerns, Iranian news agency Mehr said earlier.

The letters were “an ultimatum” to either sign long-term contracts (for a period of two to five years) or be deprived of supplies. Mehr did not specify which companies received the letter.

Foreign ministers and leaders of 27 EU countries approved a boycott on oil supplies from Iran at a meeting in Brussels on January 23. They have agreed to end all oil imports from Iran by July 1.

Greece, Italy and Spain are the European countries most dependent on oil imported from Iran.

Qalebani warned in January that the EU embargo would push up oil prices to 150 dollars per barrel.

U.S. and Western powers fear Iran wants to make nuclear weapons, something Iran has always denied.