Canadian Conservative Leader Andrew Scheer says his support for Britain's departure from the European Union is undiminished, despite the chaos Brexit has sown in British politics.

The United Kingdom was plunged into uncertainty Thursday as Prime Minister Theresa May's new Brexit deal with Europe met a rash of criticism. Two cabinet ministers resigned, the British pound fell sharply, and part of May's own Conservative caucus was trying to take her out. All over a negotiated deal for Britain to leave the European Union that critics say will leave the country bound to rules made by the European Union but without a say in how those rules are made.

Scheer said his support for Britain's move out of the EU rests not on economics or the practicalities of trade but rather on the principle of sovereignty.

"I do believe that the U.K. over the years has given up a tremendous amount of sovereignty," he said in an interview. "The bureaucratic nature of the EU, the different levels of government, the fact that court decisions in the U.K. can be appealed to a higher level of court in Europe, those are all things I don't think Canadians would ever accept for ourselves."

The British voted to leave the European Union by 52 per cent to 48 per cent. But exactly how Britain should leave Europe hasn't been settled and time is running out.

If Britain and the EU can't agree on terms for Britain's departure, the country will be propelled out of the union in March with no rules for how goods or money or people will move across Britain's border. Under a "hard Brexit," Britain and the remaining EU countries will be bound together by just the most basic of global treaties.

Scheer published an op-ed in June 2016, supporting the idea of Brexit just before the British voted. He said he hasn't followed the twists and turns of the Brexit negotiations all that closely but he still firmly believes Britain should leave the European Union because he doesn't think nations should give up important decision-making powers to citizens of other countries.

Fight against protectionism

While some international agreements give their participants shared influence or create dispute-settlement mechanisms, neither is the same as having an entirely new level of government where people in other countries can dictate what happens in your own, Scheer said.

"There is a difference between influence and direct control," he said. "I don't think that if Justin Trudeau came back from the NAFTA negotiations with a new clause — 'Oh, by the way, there's going to be a new legislature that Americans will send members to that will pass laws that will bind Canada' — I don't believe Canada would ever go for that."

Scheer acknowledged Canada has signed comprehensive trade agreements recently with Europe and with Asia, and now a new North American trade agreement is on the table. But regardless whether Conservatives or Liberals were negotiating, Canadians insisted on the supremacy of Parliament and Canadian courts in Canadian affairs, he said.

Despite his skepticism of the European Union, Scheer said he's a free-trader and warned that Canadians can't ignore the rise of anti-free trade rhetoric in many countries, including the United States.

"The takeaway from this last round of trade negotiations and what's going on in the world is we can't assume the case for free trade is made and then leave it alone. We have to be vigilant against protectionism and be constantly making the argument for free trade," he said.

"There will always be those that may not believe in those arguments so we have to be very proactive that Canada is always touting the benefits of free trade, not just to Canadians but to Americans, so it is less likely for protectionist policies to take hold in countries we trade with."