After more than a week of expressing worsening upset about China's arrests of two Canadians, Foreign Affairs Minister Chrystia Freeland on Friday formally demanded that Michael Kovrig and Michael Spavor be let go.

"We are deeply concerned by the arbitrary detention by Chinese authorities of two Canadians earlier this month and call for their immediate release," Freeland said in a written statement.

Kovrig and Spavor were taken into custody on security grounds just days after Canadian authorities in Vancouver arrested Meng Wanzhou, a senior executive with Chinese firm Huawei Technologies, so she can be extradited to the U.S. to face fraud charges.

The United States alleges Meng lied to American banks about a corporate manoeuvre supposedly designed to get around U.S. sanctions against Iran; law-enforcement officials asked Canada to arrest her when she transited through Vancouver on her way to Mexico.

She has since been released on $10 million bail.

Western analysts say China's detention of the two Canadians is clearly retaliation for Meng's arrest.

"Canada is a country governed by the rule of law," Freeland said. "Canada is conducting a fair, unbiased and transparent legal proceeding with respect to Meng Wanzhou, Huawei's chief financial officer. Canada respects its international commitments, including by honouring its extradition treaty with the United States. The rule of law is fundamental to all free societies; we will defend and uphold this principle."

Kovrig's employer says the Canadian has not been given access to a lawyer while in custody.

Karim Lebhour, a Washington-based spokesman for the International Crisis Group, says Kovrig's arrest — for allegedly endangering Chinese security — is unjustified and he should be released immediately.

At the very least, Lebhour says, Kovrig should be allowed to see a lawyer and receive regular consular visits from Canadian officials.

Kovrig served as a diplomat in China until 2016 and had been working for the Crisis Group, a non-governmental agency.

A source familiar with the conditions of Kovrig's detention says he is questioned three times a day and kept in a room with the lights on continuously.

The source was not authorized to speak publicly about the situation due to the sensitivity of the matter.

Kovrig's supporters say he was working openly, had met numerous Chinese officials, attended conferences and appeared in the media.

Spavor is director of the Paektu Cultural Exchange and one of the few people from the West to have met North Korean leader Kim Jong Un.

John McCallum, Canada's ambassador to China, has met, at least briefly, with both Kovrig and Spavor.

A third Canadian was also recently detained in China, though her case is said to be unrelated to the other two.

Canada's allies backed Freeland on Friday, suggesting a co-ordinated effort.

Britain's Foreign Secretary Jeremy Hunt said that he's "deeply concerned by suggestions of a political motivation for the detention of two Canadian citizens by the Chinese government. I call for them to be treated in a fair, unbiased and transparent manner."

U.S. Secretary of State Mike Pompeo has called for Kovrig and Spavor to be freed but the State Department repeated the sentiment Friday.

"We share Canada’s commitment to the rule of law as fundamental to all free societies, and we will defend and uphold this principle. We also express our deep concern for the Chinese government’s detention of two Canadians earlier this month and call for their immediate release," spokesman Robert Palladino said in a statement titled "Canada's Legitimate Arrest of Huawei CFO Meng Wanzhou."

In yet another statement this week, the directors of several European policy institutions in Berlin expressed "deep concern" about the detained Canadians.

"Developments such as these increase uncertainty and distrust among foreign scholars who regularly conduct research within China, as they fear for their safety," the statement said. "This will clearly undermine efforts to better understand developments in China and to further constructive relations between China and other countries."

The bodies include the European Council on Foreign Relations, the Mercator Institute for China Studies and the Global Public Policy Institute.

"I wish to express Canada's appreciation to those who have spoken recently in support of the rule of law as fundamental to free societies," Freeland's statement concluded. "We share with our partners the conviction that the rule of law is not a choice: it is the bedrock of democracy. Canada will not compromise nor politicize the rule of law and due process."

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