OTTAWA – Prime Minister Justin Trudeau is appointing economic advisor Dominic Barton to be Canada's new ambassador to China with that country’s approval, at a "critical" time for the two nations.

Barton, a prominent Canadian figure on international economic matters, has advised Trudeau's cabinet, and previously chaired the Liberal government's Advisory Council on Economic Growth.

In the new position he will have a direct line to Trudeau and Foreign Affairs Minister Chrystia Freeland, and will be the face and voice of Canada in China.

Barton will provide "strategic guidance," to Trudeau, said the Prime Minister's Office in a press release announcing his pick to fill a role that has been vacant for months amid still strained diplomatic relations.

Canada has been without an ambassador since January when Trudeau asked former Liberal cabinet minister John McCallum to resign after coming under fire for twice commenting publicly and not in line with the government’s position, on Huawei executive Meng Wanzhou's legal case, after her arrest in Vancouver in December.

Canada and China have been locked in a diplomatic dispute since her arrest on an extradition request from the United States, which was followed soon after by China detaining Canadians Michael Kovrig and Michael Spavor. Trade tensions have also been strained, with China blocking Canada’s canola exports to the country and increasing its inspections of Canadian meat products.

Barton's appointment was the result of a bilateral meeting Freeland had with her Chinese foreign minister counterpart Wang Yi at an ASEAN summit in Bangkok in August.

"An expert in the region, he is exceptionally well-suited to represent Canada and advance Canadian interests at this critical time," said Freeland in the statement. Speaking with reporters later on, Freeland said that both she and Trudeau already have strong working relationships with Barton, comparing him to the recently departed ambassador to the U.S. David MacNaughton.

"One of the things that is really important in this complicated job, is to have someone doing it who can pick up the phone at any time and speak directly to the prime minister, speak directly to me. Someone who has that personal connection, and a personal connection built up over time," Freeland said. "Dominic is a person who has that level of trust."

Freeland also said that this appointment sends a key message to China: "of the importance that Canada places, that the prime minister places on this difficult and critical relationship."

Central to his new role will be advocating for the release of Kovrig and Spavor, who have now been detained for the better part of a year and are, according to the minister, "behaving with incredible dignity and resilience." He will also become involved in their consular visits, and spend time with the two men's families.

Barton was the global managing partner of consulting firm McKinsey & Co. from 2009 to 2018, and prior to that spent years in Asia, based in Shanghai and Korea for the consulting firm. He has also chaired the Seoul International Business Advisory Council for the past six years.

Questions were raised Wednesday about McKinsey and a 2018 New York Times investigation titled: "How McKinsey has Helped Raise the Stature of Authoritarian Governments."

It dug into the major company from a few angles, noting that one of McKinsey's state-owned clients helped build China's artificial islands in the South China Sea, and explored a swanky business retreat held in western China not far from where "a sprawling internment camp" held thousands of ethnic Muslim Uighurs.

Freeland said that Barton is aware that his role as an ambassador for Canada and its foreign policy will have to on centre human rights. She also shot down questions over potential conflicts of interests arising given his past positions and personal business interests, saying he has been "carefully vetted."

In the statement announcing his appointment, Barton said it was an honour to be named.

"The relationship between Canada and China is an important one, and I will work hard to represent our great country and to resolve the challenges that currently exist," he said.

Wednesday, Barton was congratulated on stage at the Toronto Global Forum when the announcement was made.

On CTV's Power Play, president of the Business Council of Canada Goldy Hyder said it will take "dialogue" to get the Canada-China relationship "back on track," but such communication has been limited without official ambassadors on either side.

Hyder, who knows Barton personally, said he is a listener and not one to hurry into a deal. He said Barton’s business acumen and strong ties in Asia are "exactly the elements that are necessary to get to a place where we can calm this relationship down, build a strategy that allows for a constructive engagement."

Jim Nickel, who had been acting as Canada's representative in Beijing, and his diplomatic team received thanks from Freeland for their work and continued service.

China currently does not have an ambassador to Canada after reassigning Lu Shaye to France at the end of June, but it is expected they will be naming a new top Canadian attache soon.

The appointment is being made just days before Trudeau is expected to call the federal election, without consultation with the opposition parties. It remains to be seen whether his pick will be upheld by a future government, should the Liberals be defeated.

Former Conservative foreign affairs minister Peter MacKay said it’s possible that under a different government the choice for ambassador could change. He said that while Barton is an accomplished business advisor whose name has been floated in the past for the position, he doesn’t have any past diplomatic experience, unlike many of his predecessors.

"This is an exceptionally challenging task for the most talented diplomat. One has to wonder whether his business acumen is going to be able to get him through some of these very, very complex files," he told CTV News.

"While we want to wish him the very best, there's a great deal at stake for many, many people," he said.