The Organization of the Petroleum Exporting Countries (Opec) oil output fell further from its highest in four years in July as US and European sanctions cut supply from Iran to the lowest in more than two decades, a Reuters survey showed.
Supply from the 12-member Opec has averaged 31.18 million barrels per day (mbpd) in July, down from 31.63 mbpd in June, the survey of sources at oil companies, Opec officials and analysts found.
Oil prices declined below $100 a barrel in June, a level favoured by Saudi Arabia and other Opec members, prompting speculation they might trim supply to prop up prices. There is little evidence to suggest this has happened in July, although the drop in output is larger than some expected to see.
"The decline by 450,000 barrels per day to 31.2 mbpd is more than expected and almost evaporates the supply surplus," said Carsten Fritsch, analyst at Commerzbank in Frankfurt.
Opec's production has declined for three months since it pumped 31.75 mbpd in April, the highest since September 2008, based on Reuters surveys. The group is still pumping almost 1.2 mbpd more than its target of 30 mbpd.
The biggest drop this month came from Iran, whose crude is subject to a European Union embargo that started on July 1. The embargo also bars EU insurance firms from covering Iran's exports, hindering imports by some non-EU buyers.
"In July, a lot of buyers didn't take crude as they were trying to get the insurance sorted out," said an industry source. "We will never know by exactly how much as the Iranians won't tell us."
According to the survey, Iran's supply slipped by 150,000 bpd to 2.80 mbpd in July. That would be its lowest output since 1988, when it pumped 2.24 mbpd, according to figures from the US Energy Information Administration.
The US and European sanctions have pushed Iran from its traditional position as Opec's second-largest producer to rank third behind Iraq, which this year is benefiting from a long-awaited expansion in export capacity.
Iraq, after sharply boosting exports earlier this year as new export outlets in the south of the country came into operation, has seen a drop in shipments of Kirkuk crude from its northern fields in July.
Output this month has fallen by 30,000 bpd, partly a result of Iraq's Kurdistan region announcing in April it was halting its exports because firms operating there were not getting paid by the central government.