04/21/2016 02:49 EDT | Updated 04/22/2017 05:12 EDT

Justin Trudeau Goes Boxing In New York City

This is the prime minister's fourth trip to the U.S. since last month.

NEW YORK — Justin Trudeau went boxing in New York City on Thursday — in the morning, he did some metaphorical parrying, then in the afternoon planned to step into a real Brooklyn ring.

The prime minister fielded a series of questions from students at New York University, some more pointed than others. One student asked how he could justify backing new oil pipelines after campaigning on climate change.

Trudeau replied that he was very explicit before the election that he backed the now-cancelled Keystone XL project. He said the best path to a clean energy future involves being flexible.

Justin Trudeau spars with Yuri Foreman during a work out at Gleason's Gym in Brooklyn, New York, April, 21 2016. (Justin Lane/EPA)

That means encouraging prosperity, spending on innovation, and policies that support clean technology — not in shutting down industries.

"That's a simplistic solution that can be very appealing," he said, of halting fossil fuel development.

"If it does then involve everyone leaving their car at home, and everyone stopping to use fossil fuels tomorrow, our world would come to a crashing halt. So we have to be a lot more thoughtful and reasonable... Do I agree that in the future we're going to have to get off fossil fuels? Absolutely. Is that future tomorrow? No it's not...

"We're very much better off doing that from a position of having a capacity to invest and research than doing it by firelight in a cave 100 years from now, when we've reached a collapse."

An 'important step'

Nearly half the students at the forum were Canadian — including one young man in a red Maple Leaf-emblazoned hockey jersey who asked Trudeau about Lester Pearson's peacekeeping legacy.

Trudeau replied that one of the reasons Canada had the clout to shape the creation of the United Nations and the design of its peacekeeping system was that it had previously fought in conventional wars.

The students greeted him with warm applause at the start and the end — even if they found some of his answers a bit light on detail.

"This was a good introduction," said Sundus Nasir, a first-year dentistry student originally from Toronto.

"There wasn't a lot of specifics. A lot of politicians do tend to do that... Just that he's here, to engage in a dialogue, I think that's an important step."

Justin Trudeau spars during a work out at Gleason's Gym in Brooklyn, New York, April 21, 2016. (Justin Lane/EPA)

She said expectations for him are high, and noted the level of celebrity he has gained outside the country. She said her friends at school are well aware of him — watching, for example, the video of him talking about quantum computing.

He is apparently gearing up for another viral-video moment.

Trudeau will be jabbing for the cameras later Thursday at the legendary Gleason's Gym — where champions Muhammad Ali, Jake (Raging Bull) LaMotta and Mike Tyson trained, albeit in the gym's previous locations.

On Friday, he will sign a climate pact at the United Nations.

This is the prime minister's fourth trip to the U.S. since last month: he has also been hosted at a White House state dinner, attended a nuclear arms-control summit and attended meetings at the United Nations.

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