The Canadian delegation in Shanghai has begun to push for the release of detainees Michael Kovrig and Michael Spavor, but the senator heading the trip says he doesn't know if any progress has been made.

"The gist of the message is that the executive branch of Canada has asked for their immediate release," Sen. Joseph Day said after a Monday meeting with Chinese officials.

His comments come as the delegation's trip faces criticism for not putting the plight of Michael Kovrig, a former Canadian diplomat and an adviser with the International Crisis Group, and entrepreneur Michael Spavor on the official agenda.

The discussion about the detainees began after Chinese officials in the meeting demanded to know why Canada was holding Meng Wanzhou, chief financial officer for Huawei Technologies, on an extradition request from the U.S., the CBC's Saša Petricic reported.

Kovrig and Spavor were detained in China in December, shortly after Canadian officials arrested Meng in Vancouver. She was later granted bail and is now awaiting court proceedings in Canada on her extradition.

"It's not business as usual and can't be business as usual so long as these two Canadians are detained." <a href="https://twitter.com/Cooper4SAE?ref_src=twsrc%5Etfw">@Cooper4SAE</a> says Canadian delegation in China conveyed serious concerns about the detention of Spavor & Kovrig <a href="https://twitter.com/hashtag/cdnpoli?src=hash&ref_src=twsrc%5Etfw">#cdnpoli</a> <a href="https://t.co/RGZKbG88L4">pic.twitter.com/RGZKbG88L4</a> —@PnPCBC

"[The Chinese officials] feel that there is politics involved in this … and I assured them that there would be no politics influencing the judges in Canada," Day said.

The fact the plight of Kovrig and Spavor wasn't on the parliamentary delegation's official agenda was criticized by one of Canada's former ambassadors to China as "completely wrong-headed."

David Mulroney, ambassador from 2009 to 2012, had said he was astounded and concerned to hear that the issue of Kovrig's and Spavor's detentions were not specifically on the itinerary for the mission hosted by the Canada-China Legislative Association.

Before departing for China on Friday, Day had said the men's detentions are "not on our agenda, but it may well come up." He said the delegates and Global Affairs Canada saw eye to eye on the benefits of the trip.

"The Chinese, I've learned through my many years involved in Canada-China relations, they build on long term-relationships. Mutual understanding and mutual benefit comes after we get to know one another," Day told CBC News before his flight departed.

David Mulroney, Canada's former ambassador to China, says he thinks it's wrong to send a message that the Canada-China relationship is 'business as usual.' (Fred Chartrand/The Canadian Press)

Mulroney, now a senior fellow at the Munk School of Global Affairs out of the University of Toronto, said China wants Canada to believe that it's important not to say or do anything that will upset the long-term relationship.

"That's completely wrong-headed ... What we have essentially is a Canadian delegation using China's talking points," he said.

"At a time when we should be saying, 'It's not business as usual. The most important thing for us is to secure the freedom of these two people who have been wrongly detained.' We're saying, 'Well, you know there are these embarrassments that come up every now and then but we have to stay focused on the long-term relationship."

Members of the delegation said the trip's itinerary (mainly meetings with policy-makers, legislators and local citizens' organizations) was set weeks ago, but it comes amidst flared tension between Ottawa and Beijing.

For weeks, Canada has called for the immediate release of Spavor and Kovrig, and referred to their detentions as "arbitrary."

But China's top prosecutor said late last week he had "no doubt" the two Canadians had violated Chinese law. China has been arguing that both men are suspected of engaging in activities that undermined national security.

Thinks trip should have been deferred

Day said Chinese legislators from the Canada-China Legislative Association paid Canada a visit a few weeks ago and the delegation is now returning the favour.

Mulroney said he thinks the trip should have been deferred based on the tone so far.

"To suggest somehow this is about parliamentary process and the rule of law, at a time when China is so manifestly ignoring the rule of law, is also not just confusing but harmful.

"While we shouldn't pound the table, we should send people who are focused really clearly on Canadian objectives and are going to advance those objectives as a priority with steely discipline in the private meetings."

Michael Cooper, one of the MPs making the trip to China, told CBC News on Sunday that it was initially meant to be an opportunity to talk with local officials, non-governmental organizations and businesses about the bilateral relationship. But Cooper also said the detention of Spavor and Kovrig means "this is not an ordinary parliamentary delegation any longer."

"The elephant in the room, so to speak, is the arbitrary detention of these two Canadians."

Another former Canadian ambassador to China said he thinks it's good the delegation went ahead with the trip to China, but agreed the parliamentarians should be forceful in raising Canada's concerns.

'It's a question of values'

"They may not agree, but at the same time, I think the delegation has to impress that we won't be able to continue to have normal relations until this has been resolved," said Guy Saint-Jacques, who was posted between 2012 to 2016.

Guy Saint-Jacques, who served as Canada's ambassador to China between 2012 and 2016, says China should know that 'we won't be able to continue to have normal relations until this has been resolved.' (CBC)

"We are at the stage where, in fact, we have to think creatively about how we can pass messages."

"Let's remember it's a question of values and Canada is a country governed by the rule of law, so this is an opportunity to repeat to the Chinese that we have no choice but to abide by the terms of the extradition treaty that we have with the United States."

Along with Day and Cooper, MPs Geng Tan, Majid Jowhari and Chandra Arya are on the trip.

Last month, federal ​Tourism Minister Mélanie Joly put off a trip to Beijing after Canada and China agreed to postpone a ceremony marking the end of their joint year of tourism.

The Canada-China Year of Tourism 2018 was developed as a partnership to promote travel between the two countries. Joly had planned to be in Beijing for the closing ceremony set for Dec. 17 to 20.