Indonesia, the top shipper of palm oil, is enforcing its latest policy of halting exports of the tropical oil across the value chain from Thursday, in what Commonwealth Bank of Australia calls “one of the biggest acts of agriculture nationalism so far during this surge in food prices.” Export restrictions will stay in place until domestic prices ease.

Access to edible oils for making food and fuel has been thrown into disarray as war in Ukraine and weather-driven supply woes reduce availability and trade flows. Indonesia’s move threatens to drive up costs even more across multiple supply chains at a time of rampant inflation. It also makes it vital that farmers in big oilseed regions like North America produce bumper crops this year. The US is already seeing robust demand for future harvests, notably from China.

“US soybean export sales for next year are off to a flying start,” according to Jack Scoville, an analyst at Price Futures Group Inc in Chicago.

Most-active soyoil futures traded around the all-time high scaled Wednesday, and canola in North America neared the record reached in March. Palm oil for July in Kuala Lumpur dropped 1.4%, after jumping more than 9% on Wednesday.

Corn futures in Chicago matched the highest price since 2012, climbing for a fourth day to as high as US$8.185 a bushel. The gains came amid “rumours that China was shopping for US offers for late summer shipment,” Karl Setzer, an AgriVisor LLC analyst, wrote in a note. Elsewhere, wheat and soybeans fell.