Oil headed lower for a fourth straight session Wednesday, with crude prices hitting their lowest levels since September, on prospects for a global trade war that could dent demand and plans by major oil producers to begin unwinding output cuts next month.

The international benchmark fell to its lowest point since 2021 after a decision by Saudi Arabia and other producers to pump more crude surprised the markets.

Oil prices fell for a third session on Wednesday as plans by major producers to raise output in April combined with concerns U.S. tariffs on Canada, Mexico and China will slow economic and fuel demand growth hammered investor sentiment.