announced that it would stop selling oil to Spain, and is considering doing the same to Germany and Italy. But as Spain was quick to point out, they've not been buying oil from Iran since January. This is not the first time that Iran has stopped selling oil to a country that had already stopped buying.
Poor Iran can't seem to come up with a better way to strike back. It won't dare cut off oil to some one who is actually still buying, as then they'd lose money. But the political field demands that they show strength of some sort.
There have been signs that the sanctions imposed by the EU, US, and other countries have been biting for two months. Iran has also at times tried to offer oil at cheaper rates to EU nations, in attempts to gain their business back.