The TransMountain pipeline expansion is approved by Ottawa and no province should attempt to hold another one “hostage” by attempting to block a federal project, Alberta Premier Rachel Notley said Tuesday.

Commenting on the results of the B.C. election, with B.C. NDP and Green Party opponents emerging as a possible government, Notley warned that any effort by a minority government or coalition with one or two seats to stall or disrupt the project would only create investor uncertainty.

Notley told reporters in Edmonton she expects Kinder Morgan Canada’s oil-and-fuel pipeline twinning project to proceed on schedule this year, despite 16 court challenges scheduled to be heard as one case at the Federal Court of Appeal in October. Alberta was granted intervenor status in the case Monday.

Notley refused to comment directly on B.C. NDP leader John Horgan’s campaign promise to use “every tool in the toolbox” to stop the project if he forms a B.C. government. The election outcome won’t be clarified until May 24, when recounts and absentee ballots determine if Christy Clark’s B.C. Liberal government will continue.

Notley said federal responsibility for all multi-province infrastructure is “a foundational principle of confederation,” and the approval comes with increased coastal spill protection. It has been approved by the National Energy Board with 157 conditions for land and marine safety.

Prime Minister Justin Trudeau approved the project in November 2017, calling it good for Canada and safe for B.C.

We understand that some people oppose the twinning of the pipeline, and I respect their opinions,” Notley said. “But I fundamentally disagree with the view that one province, or even one region, can hold hostage the economy of another province, or in this case, the economy of our entire country.”

B.C. Green Party leader Andrew Weaver, whose three seats may hold the balance of power in a minority B.C. government, is not specifically opposed to oil pipelines. He is opposed to diluted bitumen from the Alberta oilsands being shipped in tankers, which has carried on intermittently with the existing Trans Mountain pipeline since the late 1980s.

Notley said Alberta continues to urge Ottawa to amend its legislation banning crude oil tankers from B.C.’s north coast to exclude refined products such as diesel that could be shipped from Alberta.

Kinder Morgan Canada announced in March the Trans Mountain expansion is a go commercially, after a review of oil shippers and an agreement they will pay B.C. $1 billion over 20 years in revenue sharing.