If there was total embargo yes but the Iranian regime could Export oil through Russia, Pakistan , Turkey and so on. The Persian gulf is the Easiest route. Don't forget the west is in recession any short fall will increase the oil price and deepen the recession causing further unrest in the West and the world as a whole.
Turkey launches heaviest air strikes on PKK since campaign began, official says (Reuters)
from the article: Iran could easily block vital oil route, admiral warns