Beijing ignored a personal attempt by Prime Minister Justin Trudeau earlier this year to arrange a conversation with China's premier in order to intervene on behalf of Canadians detained in China, CBC News has learned.

"You are reaching out to Prime Minister Li Keqiang," begins a Jan. 11 briefing note to Trudeau, drafted in preparation for that phone call.

Li is China's head of government and its chief administrator, overseeing the day-to-day operations of the nation. (China's premier is also referred to as 'prime minister'.)

Trudeau's office confirms that the prime minister requested the meeting, but China ignored and ultimately rejected his request.

A spokesperson for the Prime Minister's Office said Trudeau requested the call prior to a sentencing hearing for Robert Schellenberg, a Canadian man accused of drug smuggling in China.

"In advance of the January 14 sentencing hearing for Robert Schellenberg, the Prime Minister requested a call with Premier Li Keqiang, so that he could personally advocate for clemency in this case as well as reinforce our repeated call for the immediate release of Michael Kovrig and Michael Spavor," said PMO spokesperson Chantal Gagnon in a statement.

Michael Spavor, left, and former Canadian diplomat Michael Kovrig, right, are being held by Chinese authorities. (The Associated Press/International Crisis Group/The Canadian Press)

Businessman Michael Spavor and former diplomat Michael Kovrig were detained separately in December, shortly after Canada arrested Huawei chief financial officer Meng Wanzhou in Vancouver on a U.S. extradition warrant.

Trudeau has condemned the detention of the Canadians as "arbitrary."

Following the rejection of Trudeau's request for phone conversation with Li, a Chinese court sentenced Schellenberg to death in a sudden retrial, escalating an already tense situation.

Secret diplomacy

The heavily redacted 10-page briefing note prepared in advance of the call — dubbed "Outreach to Prime Minister Li Keqiang of China" — provides the first public glimpse into Trudeau's behind-the-scenes efforts to engage the Chinese government directly. It involved the highest level of Canada's bureaucracy and was led by Greta Bossenmaier, Trudeau's national security and intelligence adviser.

The note, marked "secret", was obtained by CBC News under the federal Access to Information Act.

It outlines preparations that took place as the diplomatic rift between the two countries deepened.

Trudeau and Li last met in late 2018 at the ASEAN summit in Singapore, something the prime minister's advisers saw as an opening for discussion.

"It was a pleasure to see you in Singapore in November. It was a good opportunity to review the many important mutually beneficial areas of cooperation," say the suggested introductory talking points prepared for Trudeau and listed in the briefing note.

The Chinese Embassy in Ottawa and the Chinese Foreign Ministry in Beijing did not immediately respond to CBC News' request for comment about Trudeau's request.

Cold shoulder

Roland Paris, a former foreign policy adviser to the prime minister, said the documents suggest the rejection is all part of China's strategy.

"If indeed China refused to arrange this call, then it would be consistent with China having frozen communications between our two countries, including at very high levels," said Paris, now an associate professor of public and international affairs at the University of Ottawa.

"Canada is stuck in an extremely difficult situation with very little leverage, and our relations with China will probably remain frozen, at least until Ms. Meng's extradition hearing is resolved."

“The Chinese have been very successful in creating the impression in Canada and elsewhere that a call or a meeting with one of their leaders is something that’s good in itself, it’s something that you should pay for in diplomatic terms,” said <a href="https://twitter.com/David_Mulroney?ref_src=twsrc%5Etfw">@David_Mulroney</a> <a href="https://twitter.com/hashtag/cdnpoli?src=hash&ref_src=twsrc%5Etfw">#cdnpoli</a> <a href="https://t.co/a8zNxLx9af">pic.twitter.com/a8zNxLx9af</a> —@PnPCBC

In the weeks following the rebuffed call, Trudeau and Foreign Affairs Minister Chrystia Freeland held dozens of high-level discussions with foreign heads of government, ministers and diplomats in an effort to rally an international coalition of countries to publicly speak out in support of the detained Canadians.

At home, Trudeau has been under increasing pressure, particularly from Conservatives, to reach out to the Chinese leadership.

"I actually think that by picking up the phone and having that kind of conversation, we might be able to defuse the situation," Conservative Leader Andrew Scheer said.

Trudeau 'isn't taken seriously' - Raitt

Today, Conservative deputy leader Lisa Raitt said the snub by Beijing only proves that Trudeau isn't "taken seriously on the world stage."

"It's pretty serious when your prime minister can't get a phone call with another world leader," she said. "If he can't get a phone call with the premier of China, that's just going to show them how ineffectual he is."

PM Justin Trudeau says he hopes that there will be an opportunity to engage with Chinese President Xi at the upcoming G20 meetings to discuss the ongoing dispute with that country. 0:55

Last week, the prime minister said he was considering "engaging directly" with Chinese President Xi Jinping as tensions between Canada and China continue to smoulder.

"I look forward to being at the G20 in a few weeks as an opportunity to engage with a number of world leaders with whom we have either good working relationships or challenges," Trudeau said June 6, speaking about the upcoming gathering in Japan. "The opportunity to engage with the Chinese president directly is certainly something that we are looking at."

The G20 will meet in Osaka at the end of the month.

Freeland said she repeatedly tried and failed to get a meeting with her counterpart, Chinese Foreign Minister Wang Yi.

"It's very clear that this is a very difficult moment in the relationship between Canada and China," she told CBC Radio last month.

"I have sought repeatedly a meeting with Wang Yi, the foreign minister, my counterpart. Thus far that meeting hasn't happened. But if Chinese officials are listening to us today, let me repeat that I would be very, very keen to meet with Minister Wang Yi or to speak with him over the phone at the earliest opportunity."

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