Former prime minister Brian Mulroney believes Prime Minister Justin Trudeau鈥檚 positive relationship with U.S. President Donald Trump is Canada鈥檚 secret weapon when it comes to renegotiating the North American Free Trade Agreement.

The former Conservative prime minister said he knows first-hand that Trump is pleased with his Canadian counterpart. He also expressed confidence that Canadian negotiators are on the right path to achieve a trilateral trade pact, in spite of the various dust-ups over key issues.

鈥淚 think that the relationship that Prime Minister Trudeau has developed with President Trump is a very good one, one of the best of industrialized leaders in the world,鈥 Mulroney told CTV Power Play host Don Martin on Tuesday. 鈥淗ow do I know that? Because President Trump told me after some meetings with Prime Minister Trudeau. That is our ace-in-the-hole in many ways.鈥

Mulroney invoked a mix of nostalgia and numbers in his defence of NAFTA before the U.S. Senate Committee on Foreign Relations in Washington earlier on Tuesday.

He recalled a time during his tenure when Canadians worried they would have their 鈥渃lock cleaned鈥 if a trade agreement was struck with the United States and its comparatively massive economy.

鈥淪o what happened? Trade in goods and services between our two countries exploded 300 per cent. Millions of jobs were created in both countries, and the relationship grew to be the largest such bilateral agreement in any two nations in the history of the world,鈥 he told the committee members.

鈥淎t one point a few years ago, there was more business going from Windsor, Ont. to Detroit, Mich., there was more business going across that one bridge, than America did with the nation of Japan.鈥

Mulroney elaborated on how the trade pact, which grew to include Mexico in 1994, not only enriched the three nations, but is globally envied for its role in cementing peace, prosperity and cooperation on the North American continent.

His comments follow the latest round of NAFTA negotiations in Montreal last week. The talks indicated modest signs of progress and constructive dialogue, but the way forward is still far from clear.

A number of factors loom in the background, including Canada鈥檚 World Trade Organization challenge against Washington, Canada鈥檚 signature on the new Trans-Pacific Partnership, and Trump鈥檚 persistent threats to pull the United States out of the deal.

Taking aim at Trump鈥檚 assertion that NAFTA has been 鈥渧ery, very bad鈥 for U.S. economic interests, Mulroney highlighted the plunging unemployment south of the border.

The U.S. unemployment rate remained at 4.1 per cent for a third straight month in December, the lowest level since 2000, according to .

鈥淲ith an unemployment rate of 4.1 per cent, the lowest of any nation in the industrialized world, it is becoming increasingly difficult to seriously argue that the U.S. has done poorly with its international trade agreements,鈥 Mulroney said.

He went on to describe North America as 鈥渢he largest, richest, most dynamic free trade area in the world.鈥

鈥淲ith less than seven per cent of the world鈥檚 population, the NAFTA partners last year represented 28 per cent of the total wealth in the world,鈥 Mulroney said.

He fondly quoted former British prime minister Winston Churchill鈥檚 one-time description of Canada-U.S. ties, saying, 鈥淭hat long frontier from the Atlantic to the Pacific Ocean guarded only by neighbourly respect and honourable obligations. It is an example to every country, and a pattern for the future of the world.鈥

Mulroney also referenced former U.S. president Ronald Reagan鈥檚 phrase, 鈥減rotectionism is destructionism.鈥

He applauded former U.S. presidents Reagan, George H.W. Bush and Bill Clinton for their part in shepherding the NAFTA deal since its inception.

鈥淭hey understood that such trade agreements are a vital constituent part of an enlightened foreign policy, not isolated variables to be picked apart on a profit and loss basis,鈥 Mulroney said. 鈥淪uch agreements succeed only when all parties benefit. Who can deny that that is the case here?鈥