A former TransCanada Corp. executive thinks Jason Kenney should put his anti-carbon-tax crusade on hold and prioritize the Trans Mountain pipeline expansion project.

“Everybody knows that the federal government has the capacity to impose a backstop carbon price … Alberta is going to have to endure a carbon tax applied by the federal government, and Jason Kenney knows this,” former TransCanada executive vice president Dennis McConaghy told BNN Bloomberg in an interview Monday.

“He also knows that the most important thing for Alberta is to get TMX to construction this year, given that that’s the only pipeline of any major scale that is still in the hands of Canadians to decide.”

The Alberta premier-elect’s vow to kill the federal government’s imposition of a carbon tax on Canada’s provinces served as one of the key platforms that helped Kenney’s United Conservative Party win a majority government in last Tuesday’s provincial election.

The federal government delayed its deadline to rule on the re-approval of the Trans Mountain expansion on Thursday to June 18 from May 22.

McConaghy stressed the importance of Trans Mountain’s approval, since the province is still awaiting the green light for the construction of the Keystone XL pipeline.

“We all recognize that it would be very fortuitous if KXL can finally get to construction this quarter, but we’re almost in May and there has not yet been an announcement on that,” McConaghy said. “So, it’s critical that TMX is reapproved.”

McConaghy added that learning to play nice with Prime Minister Justin Trudeau could ultimately benefit Kenney’s economic agenda for Alberta.

“It would be important for Jason Kenney to relate to Justin Trudeau in a fashion over the next two months,” McConaghy said.

Kenney has previously attacked Trudeau, telling The Calgary Sun last May that Trudeau “doesn’t have a clue what he’s doing,” calling him “an empty trust-fund millionaire.”

McConaghy said it would be better for Kenney to let his fight over the carbon tax slide to help grease the government’s wheels on the pipeline front.

“Whatever deconstruction of the Notley legacy of carbon policy and climate policy in Alberta he’s going to embark on, one [element] that he might recognize is – when it comes to carbon pricing through a carbon tax [ which is] federally imposed – that’s something that he can simply abide, avoid probably-fruitless litigation, and by doing that perhaps improve the chances that the federal government doesn’t indulge in more procrastination about that re-approval past the federal election,” McConaghy said.

“I think this is one of the great tests that he is going to have in the weeks ahead.”