“If other suppliers are willing to give up the kitchen sink, Canadian crude will suffer,” Sandy Fielden, director of research for Morningstar Inc., said by phone.

The surge in tanker bookings comes as Saudi Arabia threatened to dramatically boost oil supply after talks with Russia over a curbing supply collapsed at a recent meeting of the Organization of the Petroleum Exporting Countries, sending oil futures to their biggest crash since 1991.

Heavy crude prices in the Gulf have already weakened, with Mars’ discount to West Texas Intermediate futures at $2 on Thursday, the widest gap since July 2018, according to data compiled by Bloomberg.

Already, signs are pointing to Canadian losses in the Gulf. With limited pipeline capacity, Canadian exporters sent almost 40% of the 17.7 million barrels of crude shipped to the region on rail cars in December.

Crude-by-rail shipments are now expected to drop by 80% to 100,000 barrels a day in April, Alberta Premier Jason Kenney said on Wednesday. One oil-sands producer, Cenovus Energy Inc. announced on Tuesday that it canceled its crude-by-rail program.

The main reason for the collapse in crude-by-rail shipments is that it generally requires a price difference between heavy Western Canadian Select and West Texas Intermediate of at least $15 a barrel to be economic. Since oil prices collapsed, that discount has shrunk to less than $12.

Further price pressure could come as demand for fuel diminishes amid the carnivorous outbreak. Jet fuel consumption, already smashed by the novel coronavirus, was dealt a blow late Wednesday as U.S. President Donald Trump announced severe restrictions on travel from Europe to prevent spread of the disease.

On Wednesday, Premier Kenney said the provinces 15 month program to limit production, which has been relaxed in recent months, could be tightened with further cuts if rising crude supplies and falling prices threaten the survival of drillers in the province.

“We will use the curtailment tool responsibly to ensure at least a survival price for our producers to get through this,” he said.