The oilseed for May delivery closed down 3.1% at C$453.90 (US$338) a metric ton in New York, the biggest loss for a most-active contract since July 2016 and the lowest price since August of that year.

The Canola Council of Canada said Thursday that China had stopped all purchases of Canadian product.

The confirmation follows a March 1 statement by Richardson International that China had suspended its licenses after claiming shipments had pests and bacteria.

Trudeau says Canada will work to settle dispute

Canadian officials say they haven’t found any evidence of pests, and Richardson, the country’s top canola exporter, signalled the decision to restrict its shipments may be linked to an escalating diplomatic row with China over the detention of a Huawei Technologies executive.

Canola seeds are crushed for oil used in everything from salad dressing to deep-frying. Canola is also used as livestock feed. Data released Friday by Statistics Canada showed February crushing was down 6% from the same month last year.