OTTAWA - Agriculture Minister Marie-Claude Bibeau says she used a G20 ministers' meeting in Japan to press her Chinese counterpart for the evidence behind Beijing's bans on Canadian canola.

The overture follows last week's intervention by Canada at a major World Trade Organization meeting to demand China deliver proof that Canadian canola is contaminated.

China has stonewalled requests for Canadian experts to examine Chinese evidence that two canola shipments had pests, and there was no sign Wednesday the Canadian food inspectors would receive travel visas from Beijing any time soon.

Bibeau made clear Canada's persistent prodding of China and her Chinese counterpart would continue as the uncertainty and strain of declining Sino-Canadian relations was on full display.

"All of the G20 was about having a rule-based trade order and I'm confident that he will relay our conversation to his colleague responsible for customs China," Bibeau said.

China's rejection of Canadian food products is part of the escalating tension following the RCMP's December arrest in Vancouver of Huawei Technologies executive Meng Wanzhou. The Chinese telecom giant is at the centre of a mounting political battle, which was on display Wednesday, over whether it will equip Canada's fifth-generation wireless networks.

Nine days after Meng's arrest, China imprisoned two Canadians — ex-diplomat Michael Kovrig and entrepreneur Michael Spavor — and accused them of violating China's national security. Spavor received his seventh consular visit Wednesday, a day after Kovrig's seventh, as both men remain locked in a Chinese prison without formal charges and no access to lawyers.

Meng's arrest has outraged China's communist leaders. Meanwhile, Huawei denies the U.S. allegations that its new, next generation digital communications equipment is an organ of Chinese-state espionage.

President Donald Trump effectively banned Huawei from the U.S. on Wednesday when he signed an executive order declaring a national emergency over what the Commerce Department deemed as "threats to the information and communications technology and services supply chain by foreign adversaries."

Conservatives mounted more pressure on the Trudeau government Wednesday to follow Trump's lead and ban Huawei from supplying equipment for the Canada's fifth-generation wireless networks.

Conservative Leader Andrew Scheer said the government should have already selected one of Huawei's rivals to be Canada's next 5G provider.

"They should have made a decision much earlier. Had they done that, they could have taken this off the table," Scheer said after meeting with his caucus.

"We have two Canadians being held illegally in China. We've seen actions against Canadian canola exports now moving into pork exports," he added.

"All along the way, the government of China is escalating the situation and Justin Trudeau has done absolutely nothing about it."

Public Safety Minister Ralph Goodale said the government will take the time it needs to make an informed decision about which company it will select to serve its 5G needs.

"It is a huge enabling new technology that has enormous potential, but it also carries with it, depending on the supply chain, some significant risks," he said, "and we want to make sure that all of that is factored very carefully into a Canadian decision so we get the advantages of the technology, but we do not in any way comprise national security."

Finance Minister Bill Morneau said the government will take "a measured approach to how we deal with companies in Canada and with our international relations."

News from © The Canadian Press, 2019