A Canadian delegation in China is pressing Chinese officials to free two detained Canadians but there has been no contact between the two nations' leaders or foreign ministers despite the worst relations between Ottawa and Beijing since the Tiananmen Square massacre in 1989.

Adam Austen, a spokesman for Canada's foreign minister, said Tuesday that lawmaker Rob Oliphant is in China as part of a Parliament delegation that often visits there and that Oliphant has "raised Canada's strong concerns regarding the arbitrary detention of Michael Kovrig and Michael Spavor during his meetings with Chinese government officials."

China detained Kovrig, a former diplomat, and Spavor, an entrepreneur, in apparent retaliation for the arrest of a Chinese tech executive who is facing fraud charges in the U.S.

Canada arrested Huawei chief financial officer Meng Wanzhou Dec 1. Meng, the daughter of Huawei's founder, is out on bail awaiting extradition hearings and living in her two Vancouver mansions.

Kovrig and Spavor have been held since Dec. 10 and haven't had access to lawyers or family.

Canadian Foreign Minister Chrystia Freeland said her Chinese counterpart hasn't agreed to talk with her.

"We're not the first country to find itself in this situation with China and the Chinese practice seems to be to avoid in the early stages of these kinds of standoffs, to avoid higher level meanings," Freeland told CBC's Metro Morning radio show.

"I have sought repeatedly a meeting with the 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."

Canadian Prime Minister Justin Trudeau has not spoken to Chinese President Xi Jinping but Freeland said during the recent U.S.-China trade talks — at Trudeau's request — the detained Canadians were raised by the Americans directly with the Chinese.

"This is a very difficult moment in the relationship between Canada and China," Freeland said. "The detentions of Michael Kovrig and Michael Spavor are unacceptable."

But Freeland said Canada won't escalate the dispute.

"We do not escalate," she said. "We would like this conflict to end, but we also do not back down."

Trudeau said a news conference in Quebec that the Canadians are being held for political reasons and other nations are taking note of China's behavior.

"China is making stronger moves than it has before to try and get its own way on the world stage and Western countries and democracies around the world are pulling together to point out to that this is not something that we need to continue to allow," Trudeau said.

China has often retaliated against foreign governments and corporations in diplomatic disputes, but rarely by holding a foreign national. Beijing threatened "grave consequences" if Ottawa did not release Meng, shortly after she was detained in Vancouver in December for possible extradition to the U.S.