Trade Minister Tim Groser says he would be "astonished" if the change of the government in Canada changed anything about the Trans-Pacific Partnership deal.
Canada is one of 12 countries, including New Zealand, which reached agreement on the trade and investment pact in Atlanta two weeks ago.
It was negotiated under the Government of the Canadian Conservatives and outgoing Prime Minister Stephen Harper.
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• Canada votes for change, Justin Trudeau the new Prime Minister
Incoming Prime Minister Liberal Party leader Justin Trudeau said on the day the deal was struck that there should be more discussion, but also set out the party's free-trade credentials, saying: "The Liberal Party of Canada strongly supports free trade, as this is how we open markets to Canadian goods and services, grow Canadian businesses, create good-paying jobs and provide choice and lower prices to Canadian consumers."
Mr Trudeau's party today won an outright majority.
"At the broad level of principle," Mr Groser said, "it would be almost inconceivable that Canada would stay out of TPP."
Meanwhile, Prime Minister John Key has congratulated Mr Trudeau on his win.
"New Zealand and Canada have a longstanding and important friendship which has seen us work closely together over many years on a wide range of issues," Mr Key said in a statement tonight.
"Canada is a longstanding security partner, an important destination for New Zealand exports and an important source of direct investment into New Zealand.
"I look forward to speaking with Mr Trudeau soon to congratulate him personally. I am sure that the close relationship between our two countries will continue under his leadership."
Mr Key, Prime Minister for seven years, developed a personal friendship with outgoing Prime Minister Stephen Harper, who led Canada for almost a decade.
"He was a strong leader for Canada and I wish him all the best for the future," Mr Key said.
Canada is part of the five-eyes intelligence sharing alliance with the United States, Britain, Australia and New Zealand.
If, hypothetically, Canada had wanted to withdraw, it could have, Mr Groser said.
"There is only one real indispensable member and that is the United States."
But if major economies such as Japan, Canada or Mexico were to fail to get political support for signing the agreement, it would lead to some consequences for the negotiation.
"I would not wish to speculate on what that would be, but it would not stop it. Only the US would stop it."
Certainly it would be impossible for any country to re-negotiate any part of the deal.
Trade negotiators are now working on the legal text of the agreement.