Originally Posted by Lenny2

4th largest so what?
Go to your sources (you apparently have several of them) find out how many barrels a day they export. Then compare that to how many barrels are consumed worldwide per day.

Also, what Webby said is true as well. Iran would have to get all of OPEC to go along with them in order for oil to trade in euros (about as likely as my grandmother growing nuts and becoming my grandfather)

Of course they could leave OPEC and do whatever they want, but the effect would still be negligible.