During a surprise visit with Canadian troops in Mali Saturday, Prime Minister Justin Trudeau for the first time publicly called on China to release two detained Canadians.

Meanwhile, Opposition Leader Andrew Scheer told CTV News that he believes Trudeau should pick up the telephone and appeal to Chinese President Xi Jinping directly.

“We continue to call for the release of the detainees,” Trudeau told reporters before leaving West African country. “This is something that is extremely important to us.”

The toughening tone from the prime minister came the same day that Foreign Affairs Minister Chrystia Freeland said that Canada is instructing its ambassadors and urging its allies to push for the pair’s release.

“One point that we have been raising with our allies … is the concern about the worrying precedent that the arbitrary detention of these two Canadians sets,” Freeland said during a conference call with reporters Saturday. “That’s a point that has really resonated.”

Former Canadian diplomat Michael Kovrig and Canadian entrepreneur Michael Spavor were arrested in China days after Meng Wanzhou, chief financial officer of Chinese telecommunications giant Huawei, was detained in Vancouver on Dec. 1 at the behest of U.S. authorities.

The U.S. accuses Huawei of violating Iran sanctions. The Chinese government has accused the two detained Canadians of “engaging in activities that endanger the national security” of China, although analysts see the move as retaliation for Meng’s arrest.

Reports suggests Canadian may be facing ‘torture’

China’s foreign minister is denying reports that Kovrig is being held in a room that’s never dark and being denied access to a lawyer.

Charles Burton, an associate professor of political science at Brock University, says that if they allegations are true, they are “completely unacceptable.”

“(It’s) really a gross violation of human rights and a violation of China’s commitment to the UN convention against torture,” he said.

While it remains unknown what conditions Spavor is facing, Meng, who is out on $10 million bail, is spending her time awaiting extradition proceedings in a Vancouver home owned by her family.

Scheer suggests Trudeau pick up the phone

In an interview airing Sunday with CTV Question Period host Evan Solomon, Opposition Leader Andrew Scheer claimed that he would respond to the growing diplomatic detente by calling Chinese President Xi Jinping directly.

“I actually think that by picking up the phone and having that kind of conversation, we might be able to diffuse the situation,” Scheer said. “The Prime Minister could explain that we have independent (judicial) processes here,” he added.

China expert Lynette Ong, however, believes that a tougher Canadian approach would likely have little effect on Chinese authorities.

“I don’t think they would just back down with a few statements coming from various foreign ministries,” said Ong, who is an associate professor of political science at the University of Toronto.

“The reason I say that is because I think the arrest of the Canadians was also a political strategy on the part of Chinese authorities,” she added.

With files from The Canadian Press