Angola rejected a new output quota handed to it by OPEC and said it planned to breach it, a rare challenge to the cartel that heralds more infighting ahead.

“We will produce above the quota determined by OPEC,” Angola’s OPEC governor Estevao Pedro said in an interview on Thursday. “It is not a matter of disobeying OPEC; we presented our position, and OPEC should take it into consideration.”

A spat over African members’ quotas delayed the latest OPEC meeting by four days, and a decision was finally reached on Thursday. But after a review — pledged back in June after another fraught meeting in which the Africans lost out to other members — Angola has been handed a quota it doesn’t think is fair.

Angola, Africa’s second-largest crude producer, will pump 1.18 million barrels a day from January, Pedro said, above the 1.11 million quota set out in the OPEC agreement on Thursday.

In June, Angola, Congo and Nigeria were pushed by Saudi Energy Minister Prince Abdulaziz bin Salman to accept reduced output targets for 2024 that reflected their diminished production capabilities. The deal in June was only reached after the countries were promised an audit. But the review reflected lower capacity — and as a result a lower quota.

Pedro said last week that the country would remain an OPEC member despite the dispute. On Thursday, he sounded less sure.

“The question of whether Angola remains in the OPEC is a decision at the highest level of authority,” he said.

The defiance will bring back troubling memories of Ecuador’s exit from the group. The South American producer said it would breach its quota in 2017, and eventually ended up leaving.

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