West Texas Intermediate futures dropped 3.3% to settle at $86.61 a barrel on Thursday. Investors are focusing on tightening monetary policy around the world that could crimp economic growth and hit oil demand. The lockdown of the Chinese megacity of Chengdu to contain a Covid-19 outbreak added to the negative sentiment.

“The oil benchmarks have started September lower as signs that the global economy is heading towards murky waters grow ever-more apparent,” said Harry Altham, an energy analyst for StoneX Group. “There has been a wider shift away from risk assets in recent days and this has accelerated as bets are on” for a 75-basis-point rise in US interest rates next month.

Oil declined by more than 20% in the three months through August, overturning all of the gains since Russia’s invasion of Ukraine at the end of February. The slump prompted Saudi Arabia to signal that the Organization of Petroleum Exporting Countries and its allies could cut supplies. The group is scheduled to gather on Monday to discuss output policy.

“What it could translate into is OPEC potentially once again cutting production if prices get too low,” said Ole Hansen, Saxo Bank’s head of commodity strategy. “That makes me believe that the downside is limited ahead of Monday’s meeting.”

Among the items that OPEC+ ministers may weigh up is a US-led plan to cap the price of Russian crude in a bid to deprive Moscow of funds amid the war in Ukraine. The proposal has been gathering support, with the UK government signaling its approval. Group of Seven finance ministers including US Treasury Secretary Janet Yellen are due to discuss the proposal on Friday.

Strength in the greenback has added to headwinds for dollar-denominated commodities as the pricier currency makes them more expensive for overseas buyers. The Bloomberg Dollar Index rose toward the highest level on record following a run of three monthly gains.