China last week detained two Canadians — Michael Kovrig, a former diplomat and an adviser with the International Crisis Group (ICG), and businessman Michael Spavor — after Canadian police arrested Huawei Technologies Co Ltd's chief financial officer, Meng Wanzhou , on Dec 1.

A former Canadian diplomat detained in China is being denied legal representation and is not allowed to turn the lights off at night, people familiar with the situation said, offering new details on the highly charged and closely watched case.

Canada arrested Meng at the request of the United States, which is engaged in a trade war with China. Meng faces extradition to the United States to face fraud charges which carry a maximum sentence of 30 years jail for each charge.

China has given only vague details of why they have detained the two Canadians, saying they are suspected of engaging in activities that endangered China's security, and has not drawn a direct link to Meng's arrest.

Canada has said the detentions are unacceptable and U.S. Secretary of State Mike Pompeo has said China should free the men. ICG President Robert Malley also called for Kovrig's release on Saturday.

The sources familiar with Kovrig's case said the Canadian was taken away around 10 pm (1400GMT) on Monday last week while on the street in Beijing.

China formally notified the Canadian government of Kovrig's detention two days later, at 4 pm (0800GMT) on Wednesday last week. Canada only gained consular access to him at a police station on Friday last week, when he was visited for half an hour by the Canadian ambassador and two other Canadian diplomats, the sources said.

He is not allowed to apply for bail and not allowed to see a lawyer, said one source, adding Kovrig is questioned every morning, afternoon and evening, not allowed to turn the lights off at night, and is being held at an undisclosed location.

He is also only allowed one consular visit a month and is not allowed to see family or loved ones.

He is physically alright but tired and stressed, but physically he does not appear mistreated, the source said.