he dispute between Iran and the Western economies has escalated after Tehran warned it will stop oil sales to "some countries".
Rostam Qasemi, Iran's oil minister, said the curbs will be implemented soon but did not mention specific countries.
The warning comes just days after the European Union (EU) agreed to stop importing Iranian oil from 1 July.
The US and EU have been trying to target Iran's oil exports as part of sanctions against it.
"Soon we will cut exporting oil to some countries," Mr Qasemi was quoted as saying by the state news agency IRNA.'Arm twisting'
The EU agreed to stop importing all oil from Iran on 23 January. However, the embargo is scheduled to come into place only on 1 July, so that member states have enough time to find alternate sources of supply.
Analysts said that if Iran stopped selling oil to some EU nations on a short notice, it may create problems for the affected countries.
They said that Tehran was using this tactic in a bid to ease pressure on itself.
"I think this is a case of arm twisting. They are trying to turn around the conditions for negotiations," said Ker Chung Yang of Phillip Futures.
Mr Ker noted that despite all the rhetoric, the threat was unlikely to have any significant impact.
"I don't think this is going to work as they have a history of not following up on any extreme measures that they warn against."