British Columbia on Feb. 22 edged back from its pledge to block increased shipments of crude oil through the Pacific Coast province, saying it is now pursuing legal advice on whether it has jurisdiction to impose the temporary ban.

The province sparked a trade war with neighboring Alberta in January, when it announced numerous new environmental rules, including plans to bar any increase in heavy oil shipments while a panel studied the impact of heavy oil spills.

“We believe it is our right to take appropriate measures to protect our environment, economy and our coast from the drastic consequence of a diluted bitumen spill,” British Columbia Premier John Horgan said in a statement. “And we are prepared to confirm that right in the courts.”

The proposed rules were seen as a direct attack on Kinder Morgan Canada’s CA$7.4 billion (US$5.8 billion) Trans Mountain pipeline expansion, which would nearly triple capacity on an existing pipeline from Alberta’s energy heartland to a Metro Vancouver port.

In response, Alberta’s premier, Rachel Notley, imposed a ban on the sale British Columbia wine, and called on the federal government to step in to assert its jurisdiction over the project.

The Trans Mountain expansion was approved by Canada in 2016, but has been repeatedly delayed by permitting issues.

Horgan said his government is retaining legal counsel to pursue the jurisdictional issues in court, but that the process could take several weeks. In the meantime, the province will proceed with the other measures around oil spill preparedness, response, and compensation.