In November Huawei chief financial officer Meng Wanzhou was taken into custody at a Canadian airport on a USA arrest warrant for alleged banking fraud linked to illegal trading arrangements with Iran.
The Conservative opposition has criticized the Liberal government for not doing enough to secure the release of the two Canadians, and has targeted Prime Minister Justin Trudeau for not calling his counterpart directly.
Their father, Liu Changming, is wanted in a $1.4bn (£1bn) fraud case in China and the family has said their detention is an attempt to lure him back to face charges.
Meng faces extradition to the U.S. to face fraud charges, which she denies, linked to allegations of avoiding the United States sanctions on Iran. He was allowed a brief visit by Canadian Ambassador John McCallum in Beijing.
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Chinese law makes it extremely hard for foreign non-governmental organizations to register because they have to find a local sponsor, said James Zimmerman, a lawyer in and former chairman of the American Chamber of Commerce in China. Global Affairs has so far only released the identities of three of the detained - Michael Kovrig, Michael Spavor and Sarah McIver. Kovrig's arrest becomes public on December 11.
December 11: In the morning, Kelly Craft, the USA ambassador to Canada, tells reporters it is "absolutely false" to assume a political motive behind the Meng's arrest. China is Canada's third-biggest trading partner, though dwarfed by the USA, which trades eight times that amount, and comprises 50% of all Canadian imports and exports. China says both men were suspected of endangering state security.
The Liberals spend the day outlining how the extradition process will work, reiterating that it is an independent process.
"It's not advancing any objective other than the goal of further raising doubts about China's reliability as a country that's going to follow the rule of law". The detentions are in apparent retaliation for Canada's arrest of high-tech executive Meng Wanzhou at the request of the United States. The three family members, all American citizens, arrived in China in June under U.S. passports to visit the ailing father of Liu's wife. He calls on Trudeau to reach out to the highest levels of the Chinese government.
The pair face accusations of harming national security. They have only been granted limited access to Canadian consular services.
With files from CBC, Canadian Press.