Neither gives up an opportunity to hurt the other, whenever and wherever they can, and oil seems to be their favourite playground.

With Saudi Arabia scuttling any chances of a production freeze in Doha in April, Iran has followed suit by thwarting attempts by Saudi Arabia to introduce a production ceiling on OPEC production in Thursday's meeting held in Vienna.

Iran, which is close to its pre-sanction levels of production, had earlier agreed to discuss being part of any production freeze after it reached its desired output. However, in yesterday's meeting, Iran refused to adhere to any production ceiling, which led to OPEC abandoning the idea.

Iran has been a dark horse since the lifting of sanctions, increasing its market share quickly to the surprise of many investors.

Iran has resorted to offering large discounts to its Asian customers, undercutting the Saudi and Iraqi prices to levels not seen since 2007-2008 in order to regain their market share, reports Reuters.

Iran shipped 2.3 million b/d in April 2016, the highest level since 2012. These figures are 15 percent higher than the International Energy Agency (IEA) forecast. Iran has been successful in its strategy until now, but increasing its market share further might prove difficult.