However, OPEC's fragile control over its member states appears to be slipping with the Iranian oil minister Bijan Zanganeh openly announcing that his country's oil production had increased to 4.2 million bopd, half a million barrels over its OPEC imposed quota of 3.7mmbopd, and that most likely it would not stop there.

Ironically, along with Nigeria and Kuwait, Iran is a member of the Monitoring Committee that oversees OPEC members' commitment to agreed production levels.

The latest increase is not the first time Iranian production has exceeded 4mmbopd and to make matters worse Iran is just one of a number of OPEC states in the middle of development programs aimed at increased production.

Iran currently has two key production projects in the pipeline at the Azadegan and Bangestan fields. Japan was considered to be the main contender for Azadegan, however delays due to Tokyo's concern about Iran's nuclear program mean exclusive negotiating rights have been lost.

British Petroleum (BP) and Total have been shortlisted to bid for the $2 billion Bangestan package, which aims to add 100,000bopd of new oil to existing production.

This month the National Iranian Oil Tanker Co. also ordered six new tankers worth $US240 million to increase swap volume from 100,000 bopd now to 370,000 bopd in less than two years.

Iran's open flaunting of the OPEC quotas tops a year of turmoil for the cartel following nationwide strikes in Venezuela and Nigeria, ethnic violence in the Nigerian Delta and of course the US invasion of Iraq, all of which have led to the fluctuating global crude prices.

The biggest question after the Iraq war was whether the OPEC founding nation would adhere to quotas once production resumed pre-war levels and what impact that may have on the production levels of other members.

Fortunately for OPEC that issue seems to be put on the backburner as the new Iraq administration is forced to battle continual sabotage, a decaying infrastructure and the possibility of a sectarian civil war.

Opec already expects its members' production to increase by 2.5 million bopd next year, which is above the expected rise in demand, a move which could dampen prices, yet there is little the consortium can do to call its members into line.

The next six months is shaping itself as a litmus test for the strength of the fragile union.