Rock-bottom prices for Canadian oil and a lack of demand are setting the stage for “inevitable” production cuts, according to Goldman Sachs, which says the industry could run out of storage space within weeks.

Landlocked Canadian crude could see prices go negative—meaning producers would pay customers to take the oil, analysts led by Emily Chieng said in a note to clients. Shipping it out by rail isn’t economic, and increased production from OPEC nations could displace demand for Canada’s barrels, Chieng said.

Western Canadian Select crude traded at $5.52 a barrel Wednesday morning, a $14.75 discount to West Texas Intermediate. Canadian heavy crude has become so cheap that the cost of shipping it to refineries exceeds the value of the oil itself.

The dismal economics of selling Canadian oil aren’t the biggest factor in Goldman’s forecast of production cuts. A lack of storage capacity is.

Given the loss in demand from refineries, “we expect that commercial inventory levels could be breached within 2-3 weeks if Canadian production is not reduced further,” Chieng wrote.

“Given this, it is not the challenging economics of oil sands assets in the current price environment that drives the decision to shut in production, but rather, the physical limitations of storage capacity in a demand challenged environment that will ultimately drive producers to organically curtail output,” she said.

Goldman estimates that Canadian producers have announced production cuts of about 100,000 barrels per day. Suncor Energy Inc. said last week it will shut in one of its two so-called trains at its two-year-old, 194,000 barrel-a-day Fort Hills oil sands mine. The company also is delaying the start up of its MacKay River oil sands wells to May.

The bank sees Suncor as Canada’s best positioned energy company to navigate the current environment, given its integrated business and “more resilient” balance sheet. Suncor shares have fallen 48% this year.