The current diplomatic spat between Canada and China amounts to the "worst crisis" Canada’s former ambassador to China has ever seen in diplomatic relations between the two countries.

"It's really an unprecedented situation," Guy Saint-Jacques, who served as Canada's ambassador to China from 2012 to 2016, told Don Martin during an interview for CTV's Power Play.

"It just shows how difficult it has become to deal with what I call the new China, that is a lot more assertive, arrogant and in your face," Saint-Jacques added.

Relations between Canada and China have been plunging since the arrest of Huawei CFO Meng Wanzhou in Vancouver last December. Canada arrested Meng in response to an extradition order from the United States

China then went on to detain and ultimately arrest two Canadians, Michael Kovrig and Michael Spavor, in an apparent retaliation for Meng's arrest.

"There are two Canadian men who are effectively on death row in China right now because of this," former foreign affairs minister John Manley told Martin.

According to Manley, Meng is key to this dispute. It's a sentiment echoed by Geng Shuang, the spokesman for China's foreign ministry.

"What I can say is that the current difficulties in China-Canada relations are caused solely by the Canadian side, who must assume full responsibility," Geng told reporters Thursday.

"We hope it will take China's solemn concerns seriously, release Ms. Meng Wanzhou without further delay and ensure that she returns to China safe and sound," he added.

The United States is standing by its extradition order as China continues to apply pressure on Canada, forcing Canada to navigate dicey diplomatic issues with both superpowers. While the Globe and Mail reported that former prime minister Jean Chrétien believes Canada should drop the extradition case against Meng, Foreign Affairs Minister Chrystia Freeland rejected the suggestion.

"It would be a very dangerous precedent indeed for Canada to alter its behaviour when it comes to honouring an extradition to treaty in response to external pressure," she said.

"When we think about the implications of setting such a precedent we could easily find ourselves in a situation where by acting in a single, specific case we could actually make all Canadians around the world less safe."

Saint-Jacques agreed with Freeland.

"I think this would create a very dangerous precedent that could come back to haunt the government, because Canada is a country governed by the rule of law," Saint-Jacques said.

He added that it could hurt Canada's reputation with the allies who Trudeau has reached out to for support.

However, Manley said those allies have "totally" let Canada down.

"Where have the Germans been? Have they said we’re not talking to you, China, until you talk to Canada – no. What about our other so-called progressive friends?" Manley asked.

Trump-Trudeau meeting best hope for Canada-China relations: Manley

Canada's best hope still lies with one ally, according to Manley. He said the best way out of the situation would be for Prime Minister Justin Trudeau to convince U.S. President Donald Trump to withdraw his extradition request for Meng.

"The U.S. has the key to this. They can simply withdraw their request and we all go back to starting point. She's gone, we’re off the hook, we haven't lost any kind of reputation as a result of that," Manley said.

But Manley wasn't optimistic about Trudeau's odds of winning over Trump when they meet in Washington next week.

"I don't know how you get to Donald Trump, I despair."

However, despite his doubts, he doubled down on his assertion that the key to unlocking a more positive relationship with China lies with the unpredictable U.S. president.

"The key is Ms. Meng, and the key to Ms. Meng with the least amount of face loss for Canada is Donald Trump, so I think that’s where we’ve got to start."

Trump and Trudeau are scheduled to meet on Thursday, according to the press release from the Prime Minister's Office. They’re slated to discuss the new NAFTA and the detention of two Canadians in China.