Iran warned that any breach of OPEC’s oil production ceiling will hurt the effectiveness of the organization, and urged strict adherence to the caps.

Output by some member countries in June was “far above” their original commitment and a violation of that agreement, Iran Oil Minister Bijan Namdar Zanganeh said in a letter to OPEC President Suhail Al Mazrouei, according to the oil ministry’s news service Shana. He didn’t identify those countries. OPEC and allies agreed last month to increase production to levels assigned in late 2016, effective this month.

“We are concerned that this violation may continue” for the rest of the agreement “and turn into a routine practice,” Zanganeh said.

U.S. President Donald Trump is pressing Saudi Arabia, Iran’s regional arch-rival, and some other OPEC members to fill in any supply gap that will arise when U.S. sanctions curtail Iranian crude exports. Iranian flows could be slashed in half once American sanctions take effect on Nov. 4, according to the International Energy Agency. The country ships about 2.5 million barrels a day.

SAUDI OIL 

Oil retreated below US$71 a barrel as more supply comes to the market. Saudi Arabia offered additional cargoes of its Arab Extra Light crude to at least two buyers in Asia for August, people with knowledge of the matter said, after supplying full contractual volumes to customers in the region. Meanwhile, the U.S. government is said to be mulling the release of oil from the nation’s 660-million-barrel Strategic Petroleum Reserve.

“In case the OPEC member countries do not fully adhere to their commitments, the effectiveness of this organization as the only developing countries’ intergovernmental organization with almost sixty years of history, will be gradually eroded,” Zanganeh said in the letter. “Responsibility of this would lay with those member countries violating their commitments.”

Zanganeh’s comments follows last week’s message from Iran’s representative to the Organization of Petroleum Exporting Countries, urging Trump not to use the nation’s stockpile of oil to push prices lower, and instead drop sanctions on Iran’s crude exports.