This story has been updated.

The Canadian election Monday ousted a strong supporter of the Keystone XL pipeline. And it brought into office another strong supporter of the Keystone XL pipeline.

The new Canadian prime minister, Liberal Party leader Justin Trudeau, has supported the construction of the controversial Keystone XL pipeline as well as TransCanada’s proposed $12 billion Energy East pipeline, both of which would carry bitumen from Alberta’s vast oil sands to ports and world markets.

Trudeau has said that the pipelines should be important parts of a national infrastructure program he supports. But at the same time, he advocates the adoption of a national plan to reduce greenhouse gas emissions. Environmental groups say that the two positions are incompatible.

Trudeau has also extolled the virtues of carbon taxes, though he has also said that decisions about that might be best left to provincial governments. Many supporters of a more aggressive climate policy say that Canada’s federal government needs to take leadership on that front.

It is unclear how Trudeau’s election will affect the upcoming U.N. climate talks in Paris later this year, but it could alter the dynamics and make it easier to secure the kind of stricter agreement the U.S. and Europe have been advocating. Canada’s outgoing Prime Minister Stephen Harper consistently resisted the idea of more ambitious carbon pact, and renounced the nation’s commitments under the Kyoto Protocol. Still, Trudeau has suggested he would consult with top provincial officials before revising Canada’s overall climate goals, an approach that would likely delay any new comprehensive strategy until after the U.N. negotiations take place.

In a recent press conference discussing a congratulatory phone call he had with President Obama, Trudeau demurred when asked repeatedly about the Keystone XL Pipeline and a pending White House decision on the matter.

“I think one of the things that has been a challenge in the relationship between Canada and the United States is it has in many cases been focused on a single point of disagreement, a single potential point of disagreement, a single pipeline,” Trudeau told press.

“Any relationship as important as Canada and the United States goes beyond a single project,” he later added.

“The tone from Canada is going to be different in Paris but it remains to be seen whether there’s any new federal content or not,” said Rick Smith, executive director Broadbent Institute, an independent progressive organization.

During the election, Trudeau’s support for oil sands pipelines and oil sands development played relatively well in Alberta, where low oil prices have delayed the expansion of oil sand (or tar sand) extraction and where unemployment has climbed to nearly 7 percent, the highest level in four years. The Liberals captured four of the province’s 34 seats, up from zero. But environmental groups say that the oil sands extraction — which requires more energy to exploit and therefore emits more greenhouse gases in the process — undercuts climate change efforts and also mars Alberta’s unspoiled unique boreal forests.

“Justin Trudeau needs to know that you can’t deal with climate change and build more tar sands pipelines, especially when those pipelines don’t get any sort of climate review,” Cameron Fenton, Canadian Tar Sands Organizer with 350.org, said on the group’s Web site.

The Keystone XL pipeline would carry oil sands crude from northern Alberta to the southern border of Nebraska, where it would connect with other legs of the Keystone network leading to Port Arthur, Texas. Much of the oil would then be exported. The pipeline has become a symbol and litmus test for American politicians’ position on climate change. The Obama administration has been studying the proposal, which was first submitted seven years ago.

The Energy East pipeline would carry 1.1 million barrels a day from Alberta to New Brunswick.

During a visit to Washington in 2013, Trudeau acknowledged that his support for the pipelines might surprise some people.

“There were some people who raised an eyebrow, absolutely,” Trudeau told reporters according to a CBC report. “I’m seen as a strong, young progressive with an environmental background. The fact that I’d be talking positively about the project I think got people thinking about the fact that perhaps it’s not as bad as it’s been caricatured.”

On the carbon tax issue, Trudeau’s party has been working to adopt such taxes at provincial levels because the federal government has been so strongly opposed to one. Those taxes have been effective. According to an article in The Economist last year, British Columbia’s carbon tax, first imposed by Liberal Party provincial government in 2008 and gradually increased since then, had contributed to a 16 percent drop in fuel consumption. Because the tax must by law be revenue-neutral, British Columbia cut income and corporate taxes to offset the revenue it gets from taxing carbon. The province has the lowest personal income tax rate in Canada, according to the article.

While wanting to leave that to the provinces, Trudeau advocates national targets for greenhouse gas reductions. He also supports the establishment of a Low Carbon Economy Trust. The Trust would provide funding to projects that materially reduce carbon emissions under the new pan-Canadian framework, the Liberal Party Web site says. It would be given $2 billion in funding.

He also favors an end to fossil fuel subsidies.

Trudeau came to the election carrying some baggage from his father Pierre, who as Canada’s premier adopted a very unpopular National Energy Program.

“The environment and the economy,” the younger Trudeau has said, according to a June report by CBC News. “They go together. They go together like paddles and canoes. If you don’t take care of both, you’re never going to get to where you’re going.”

Juliet Eilperin contributed to this report.

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