OPEC oil exporters were on course to leave output policy unchanged on Friday (May 31) as oil held around the group's preferred level of $100 a barrel.

Before their closed session meeting, several oil ministers said they expected the Organization of the Petroleum Exporting Countries (OPEC) to leave its 30 million barrels per day (bpd) output target unchanged for the rest of this year.

Saudi Arabia's Oil Minister Ali al-Naimi set the stage for a swift and easy deal, saying world oil markets were in good shape and OPEC was happy with the price.

That may be the case for now but OPEC has little room to pump more oil due to the U.S. oil boom that has sparked competition for market share in Asia and set off a rivalry between its top two producers Saudi Arabia and Iraq.

A year ago, OPEC dismissed the threat of shale oil, but it's now a live topic within the 12-member group.

Gulf producers, led by OPEC heavyweight Saudi Arabia, think that OPEC will still be able to pump at least 30 million bpd, provided U.S. shale grows at a moderate pace.

Despite growing supply, oil is comfortably above $100 a barrel, well below the $125 that rang alarms in major consumer countries last year.

But oil above $100 has also freed U.S. shale oil in North Dakota and Texas - which competes with OPEC crude of similar, light quality from Nigeria and Algeria, rather than heavier Saudi output.

Nigeria, along with Algeria, has already felt pressured by the U.S. oil boom, losing ground in its most lucrative export market and diverting sales to Asia.

Iraq is also fighting for more Asian market share, competing with regional rival Saudi Arabia. But Iraq's production and exports are not growing as swiftly as hoped due to myriad infrastructure and logistical hurdles.

Oil Minister Abdul Kareem Luaibi expects the country's oil fields to ramp up to about 3.5 million bpd by the end of the year, up 400,000 bpd on current rates.

When OPEC last met in December, he expected average production of 3.7 million bpd for this year. The more modest growth has relieved concern among core Gulf producers that Baghdad would capture their market share in Asia.

Presented by Adam Justice