China halted imports of Canadian meat after an investigation into traces of a banned feed additive led to the discovery of counterfeit health certificates attached to a pork shipment.

The forged documents were sent to Chinese regulatory authorities through Canada’s official certificate notification channel, which reflects “obvious safety loopholes,” the Chinese embassy in Canada said in a statement posted online. Marie-Claude Bibeau, Canada’s minister of agriculture and agri-food, confirmed in an email that “inauthentic export certificates” were used.

China has requested the Canadian government suspend the issuance of certificates for meat exported to the Asian nation as of June 25.

“We hope the Canadian side would attach great importance to this incident, complete the investigation as soon as possible and take effective measures to ensure the safety of food exported to China in a more responsible manner,” the Chinese embassy said in the post. The Canadian Pork Council said in a separate statement that it’s hopeful talks between officials from both countries will “lead to a quick resolution” of the dispute.

The suspension puts a sharp break on the surge in Canadian pork exports so far this year as producers rushed to fill a protein gap created by the spread of African swine fever in China, the world’s top pork consumer. The move also comes at time of escalating tension between the nations after Canada arrested Huawei Technologies Co. Chief Financial Officer Meng Wanzhou at the request of U.S. authorities last year. China has since detained two Canadians and revoked canola import licenses for two Canadian exporters, citing pests being found in shipments.

Canada’s pork exports this year have so far jumped 50% over the 2018 level of C$514 million ($390 million), according to the statement from the Canadian Pork Council. China was Canada’s third-largest export market last year.

The banned additive, ractopamine, was first reported to have been found in a shipment of frozen pork products from Quebec processor Frigo Royal on June 18. Ractopamine is banned in most countries. It is used to make hogs gain muscle faster while eating less grain.

The Canadian Food and Inspection Agency “has taken measures to address this issue and is continuing to work closely with industry partners and Chinese officials,” Bibeau said.