Ottawa has called in police to investigate a falsified export certificate after China banned imports of Canadian meat over the discovery of a banned substance in frozen pork.

The issue of the falsified documents has been referred to the RCMP, Agriculture Minister Marie-Claude Bibeau said in an interview Wednesday. Ms. Bibeau said she’s optimistic about a quick resolution to the ban.

“We were hopeful it wouldn’t happen, but I can’t say it was a surprise either,” she said. “We were conscious it was a possibility, and we did our best to avoid it.”

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International Trade Minister Jim Carr said Wednesday investigators don’t yet know where the pork came from. The Quebec-based company Frigo Royal named by Chinese officials handles shipping and distribution, and does not produce pork. (A spokesperson for Frigo Royal declined to comment Wednesday.)

Mr. Carr suggested the pork may have originated from outside Canada. “Somebody is trying to use the Canadian brand to move product into the Chinese market," he said.

A spokesperson for the RCMP could not confirm an investigation has been launched, saying it does not typically confirm investigations unless charges are laid.

At issue is a shipment of frozen pork tongues that was sent from Canada to China in mid-June. After testing, Chinese officials found the presence of ractopamine, an additive that accelerates lean muscle growth and is approved for use in Canada, though infrequently used. In China, Europe and Russia, ractopamine is prohibited.

Chinese officials notified the Canadian Food Inspection Agency, which conducted an investigation. That probe found that the export certificates – which would have required certification of a ractopamine-free environment – were “inauthentic.”

Ms. Bibeau said the agency was able to determine quickly that the documents were falsified, because of numbers that did not match with those used in the government’s internal systems. She added that the falsified documents were specific to a system used only for meat exports to China, so she is confident other countries have not been affected.

The temporary ban affects all Canadian meat exports to China – Canada exported $611-million worth of pork and beef to China last year. This follows a ban China had already placed on Canadian canola about three months ago. It also further worsens the relationship between the countries, after the December arrest in Vancouver of Huawei chief financial officer Meng Wanzhou and directly ahead of the Group of 20 leaders’ summit in Japan, which starts Friday.

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Officials in Ottawa and Beijing have been in daily contact over the past week in an effort to quietly address the discovery of the banned substance and the falsified certificate. So the Canadian officials were taken aback when China thrust the incident into full public view this week, according to a government source who was not authorized to speak on the matter.

A senior official said that Prime Minister Justin Trudeau, who was travelling to the G20 summit Wednesday, aims to raise the ban with Chinese President Xi Jinping once there – but only if he’s able to secure a meeting. The official was granted anonymity because they were not authorized to speak on the matter.

U.S. President Donald Trump has promised to press Mr. Xi at the G20 summit about Canadians Michael Kovrig and Michael Spavor, both of whom were arrested in apparent retaliation over Canada’s detention of the Huawei executive.

China’s move comes at a time when its own domestic pork supply has been threatened by an outbreak of African swine fever, leading to the culling of millions of pigs. This, according to some experts, means China – where the diet of many citizens is heavily reliant on pork – might be amenable to a relatively quick resolution.

“I think China would very much like to import our product,” said Al Mussell, the research lead at Agri-Food Economic Systems. "They’re in a desperate situation.”

But others pointed to the deepening dispute between Ottawa and Beijing as evidence this is unlikely.

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“It’s fair to say that how long it takes to normalize Canada’s meat exports will largely depend on the normalization of China and Canada’s diplomatic relations – or at least an easing of tensions," said Lin Rongquan, a Chinese veterinary health expert and former researcher for the Shanghai Meat Trade Association.

China’s Foreign Ministry on Wednesday did little to dispel that notion, reiterating its call for Ms. Meng to be set free even as it demanded Canada address shortcomings in its agricultural exports.

Asked about the meat ban, Foreign Ministry spokesman Geng Shuang said “relevant Chinese authorities act in accordance with laws and regulations. We hope the Canadian side attaches great importance to the fake certificate case, completes the investigation as soon as possible and takes effective rectification measures to ensure the safety of food exported to China.”

He then added that “our position is very clear” on Ms. Meng.

“We ask the Canadian side to take China’s concerns seriously, immediately release Ms. Meng Wanzhou and allow her to return to China safely.”

With reports from Rachel Emmanuel in Ottawa

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