China’s refiners, all but cut off from Venezuelan crude in the past week as the US positions itself for access to the world’s largest oil reserves, are eying a pricier alternative source — Canada.

Energy experts say President Donald Trump’s push to revive Venezuela’s oil market boosts the United States' leverage with China, while putting Canada at a disadvantage.

Canadian crude prices on the U.S. Gulf Coast plummeted Wednesday, Bloomberg reported, after President Trump said Venezuela would give up 30 million-50 million barrels of oil to the U.S. that would be sold at market prices.

Canadian heavy oil prices are plunging this week following the upheaval in Venezuela over the weekend and the prospect of more Venezuelan oil imports to the United States.

The Canadian dollar weakened for a seventh straight day against its U.S. counterpart on Wednesday as the prospect of increased Venezuelan oil exports undercut the appeal of the commodity-linked Canadian currency.

Robert Johnston, director of energy and natural resources policy at the University of Calgary’s School of Public Policy, said he was heartened that the Prime Minister made the comments to help calm market fears that resulted in a selloff in Canadian energy shares on Monday.

Stocks of leading energy companies such as Suncor Energy (SU), Canadian Natural Resources (CNQ), and Imperial Oil (IMO) are down between 5% and 8% after the U.S. attacked Venezuela, captured President Nicolás Maduro, and took control of the country’s crude reserves.

American helicopters and a Coast Guard vessel were being used to board the tanker under law enforcement authority granted to the Coast Guard, while American and British submarine-