A Reuters survey released Wednesday showed that the organization of Petroleum Exporting Countries (OPEC) March crude oil production increased, due to sanctions against Iran after the abolition of the increase in supply, and southern Iraq exports close to record levels, offset by a small oil in refinery maintenance and supply interruptions caused yield reduction.

The survey also found that the largest oil exporter Saudi production has not changed significantly, this is the Saudi government seriously freeze another sign of production plan to support oil prices. Oil prices hitting $27 a barrel in January of the 12 year low, but has now rebounded to $40. Oil producing countries will be held in April 17th in Qatar met to discuss the frozen production plan.

“Frozen production plan to support oil prices,” German commercial bank analyst CArsten Fritsch said, “if the results of the meeting is disappointing, the price risk of short-term frustration.”

According to the survey, OPEC in March the supply of crude oil from 32 million 370 thousand barrels to 32 million 470 thousand barrels in February increased slightly. The investigation is based on the shipping data, and from OPEC oil company, Consultants Co and sources of information.

Was cancelled in January after the sanctions, Iran is the largest oil production increase, Iran hopes its market share back to the level before the sanctions, and said it would not join the frozen production plan.

According to a Reuters poll since December last year, Iran daily increase of 230 thousand barrels. Officials in Iran say Iran supply growth rate is far greater than the expected.

Iraqi production also increased. In March Southern exports could reach a record high, to offset oil pipeline transport crude oil from Kurdistan interrupt. Iraq is the biggest source of supply growth in 2015 OPEC.

Angola’s crude oil exports increased. In reduced production in the country, the reasons for the production and maintenance for the refinery, and not because of the initiative to limit production.

The United Arab Emirates reduced production, because the production of Moore crude oil class (MUrBAn) undergoing maintenance restricted production, maintenance will be completed in April.

To further reduce production in Nigeria, because of the Royal Holland / Shell oil group in the local branch of the business Fica Dos (Forcados) of crude oil production interruptions for a whole month, but was partly offset by an increase in other grades of crude oil supply.

Libya production due to power outages fell, the country’s oil production has been shrinking dramatically before the civil war. Venezuela supplies have also decreased slightly.

Participate in the investigation of the sources said, compared with February, the Saudi yield basically stable, steady to slightly reduce the export volume in March. On March Saudi production is expected to be 10 million 180 thousand barrels, 10 million 200 thousand barrels per day in February.

OPEC gave up the historical role of independent production to boost oil prices since November 2014, the surge in output. The hope can inhibit the development of low oil prices higher cost competitive supply output growth.

OPEC crude oil supply increased, the situation of excess global supply deterioration this year frozen production plan is OPEC and non OPEC members for the first time since 2001 in the supply policy of cooperation.