The state-owned Saudi Arabian producer will reduce the official selling price of Arab Light by US$1.05 a barrel for January from the previous month, according to the median estimate in a Bloomberg survey of six refiners and traders. That would be the biggest decline since February.

Asian physical markets have softened over the past month and global benchmark Brent has tumbled around 15% from a peak in late September, which may make it harder for the Saudis to maintain pricing levels.

There’s also been an increase in supply from the US, Guyana and the North Sea, highlighting how the kingdom’s strategy of restricting output to push up prices is putting it at risk of losing market share.

Oil from outside the Middle East is looking more attractive to Asian buyers amid strength in Dubai crude, the benchmark that most Persian Gulf crude is priced off, due to supply curbs from Opec+ producers.

Dubai and Brent are now close to parity, PVM Oil Associates data show, an unusual situation given the global benchmark is generally more expensive. West Texas Intermediate, the US marker, is about $5 a barrel lower than its Middle East counterpart.

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The responses in the survey ranged between declines of 75 cents and $2 a barrel, and were mostly based on the assumption that the kingdom will extend its 1-million-barrel-a-day unilateral output cuts into next year at the OPEC+ meeting on Thursday. Aramco typically releases its official crude prices in the first five days of the month.