"Recognizing, of course, how much the Canadian economy depends on close collaboration and integration with the American economy, anything that creates impediments at the border — extra tariffs or new taxes — is something we're concerned with," Trudeau said Thursday night in Houston, Texas.

HOUSTON — Prime Minister Justin Trudeau made it clear he is flatly against a proposed U.S. border adjustment tax, telling a global gathering of politicians and energy sector executives it would hurt the economy in both countries.

Prime Minister Justin Trudeau receives the CERAWeek Global Energy and Environment Leadership Award in Houston, Texas, on March 9, 2017. (Photo: Sean Kilpatrick/CP)

Trudeau came to the heart of the U.S. oil path to deliver a keynote address to the annual CERAWeek conference — a first for a Canadian prime minister — that attracts legislators, energy executives, innovators and experts from around the world.

His comments on the importance of avoiding a levy at the border — as proposed by Republican leadership in the U.S. — came in a question-and-answer session following a speech where Trudeau make the case for investing in Canadian natural resources, even while his Liberal government is preparing for a future without fossil fuels.

"Nothing is more essential to the U.S. economy than access to a secure, reliable source of energy," Trudeau said during his speech. "Canada is that source."

'Proud' of pipeline progress

Trudeau talked up the connection between resource development and taking care of the environment, a message he has also been taking to Canadians.

Trudeau has been trying to convince skeptics on both sides of the political spectrum that the country needs both new pipelines and a carbon-pricing plan meant to cut back on greenhouse gas emissions.

The conference, organized by London-based research firm IHS Markit, also gave Trudeau an award for his stance in favour of sustainable development.

Trudeau noted his government approved two pipelines — Trans Mountain's Kinder Morgan line and Enbridge's Line 3 rebuild — and welcomed the news that U.S. President Donald Trump wants to move ahead with the Keystone XL pipeline project that TransCanada proposed nearly a decade ago.

"Let me be very clear: We could not have moved on pipelines had we not acted on climate."

"I make no bones about it: We're proud of this. It's progress. It's important," said Trudeau.

But he argued that other things are important too.

"Let me be very clear: We could not have moved on pipelines had we not acted on climate," Trudeau said.

The visit comes at a time when the energy industry, buoyed by a recent resurgence in the price of oil, and governments around the world are grappling with a dramatic shift in American politics.

Trump has vowed to boost fossil fuel production through easing regulations. That stance, and his tough-on-trade approach could challenge Trudeau's vision for a clean-energy future.

Trudeau did not openly criticize Trump, but there were a few moments during his time on stage Thursday night where he pointedly praised the Canadian way of doing things — particularly when it comes to immigration — in a way that allowed his audience to read between the lines.

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