Wildrose MLA Nathan Cooper rose from his seat Monday afternoon and read a question scrawled hastily on a scrap of paper as an unusually sleepy question period wrapped up in the Alberta legislature.

"In just a few minutes from now, the NDP in British Columbia and the Green Party are set to announce that they are about to cut a deal to form (a) government," said Cooper.

"It’s clear that this will not be good for the interests of Alberta. Both parties said that they oppose Kinder Morgan."

Before question period, the Speaker had warned members to stay off their cellphones, but nobody paid much attention as news broke on Twitter of a deal between B.C. NDP Leader John Horgan and B.C. Green Party Leader Andrew Weaver.

The deal would see the Greens support the NDP as a minority government in B.C. for four years. The Alberta legislature was debating the issue 20 minutes before it was officially announced.

Kinder Morgan plans a $7.4-billion expansion of the Trans Mountain pipeline that would get more Alberta oil to West Coast tankers.

The project's approval has been a success story for the Alberta government and it has credited the politically unpopular carbon tax for creating an environment that made it possible.

In response to Cooper, Environment Minister Shannon Phillips accused the Wildrose Party of "getting out their pompoms and cheerleading for Alberta’s demise."

Fielding questions from B.C. reporters after the announcement, Weaver said blocking the Kinder Morgan expansion was critical to his party and its members, but the terms of the deal between the two B.C. parties — and how it addresses the pipeline — won't be available until both caucuses vote on the political partnership Tuesday.

Alberta deputy premier Sarah Hoffman told reporters it would be "very difficult" for the new B.C. government to obstruct the pipeline, given it has already been approved by the National Energy Board and federal cabinet.

Two weeks ago, Premier Rachel Notley said any government in B.C. would be over-reaching if it tried to block the pipeline.

In the wake of the B.C. agreement, Wildrose Leader Brian Jean called on the government to remove two environmentalists who have opposed the Kinder Morgan pipeline expansion from the government's oilsands advisory group.