Conservative Leader Andrew Scheer is urging Prime Minister Justin Trudeau to step up inspections on all products from China and to consider slapping tariffs on imports from the Asian country.
In a letter Friday, Scheer pressed Trudeau to take a harder line with Canada's second-biggest trading partner at a time when the countries are locked in a diplomatic dispute that has dragged on for more than seven months.
Since the start of the conflict, China has detained two Canadians on espionage charges and has taken trade-related actions against goods from Canada that carry economic consequences.
"There is no other way to put this: Canada is being bullied by the Chinese government and you have done nothing to stand up for Canada in response," Scheer wrote to Trudeau in the letter, which his office released publicly.
The Canadian Food Inspection Agency, however, has no intention of increasing inspections on Chinese imports, a spokeswoman for Agriculture Minister Marie-Claude Bibeau said later Friday.
China detained two Canadians in December just days after Canada arrested Chinese high-tech executive Meng Wanzhou in Vancouver on a U.S. extradition warrant.
Angered by Meng's arrest, China has increased inspections that have led to the suspension or obstruction of key Canadian agricultural imports, including pork and canola.
Last week, China announced an additional suspension of all imports of Canadian meat products because of claimed concerns over fraudulent inspection reports.
Canada is collaborating with China in an ongoing investigation, said Katie Hawkins, Bibeau's spokeswoman.
Scheer wants Trudeau to respond by intensifying Canadian inspections on all imports from China and to start exploring possible retaliatory levies on Chinese products that will have the greatest possible impact while "minimizing harm" to consumers in Canada.
He added that Canada imported more than $75 billion worth of goods from China last year.
"In short, we have leverage in this dispute, but only if we choose to wield it," Scheer wrote.
Trudeau, who has called the detention of the Canadians arbitrary, has tried to secure their release by encouraging Canada's allies to tell Beijing it needs to follow the rule of law and other international standards.
Trudeau's spokeswoman Chantal Gagnon said Friday the government continues to work to help the detained Canadians.
"We recognize that Canada and China are going through a challenging moment right now, but that's why having direct conversations is an essential part of how we move forward."
Gagnon also said the government continues to pursue economic opportunities for Canadians in China, "and the opportunity to create growth and progress around the world."
The prime minister and Kelly Craft, the U.S. ambassador to Canada, have said President Donald Trump raised the plight of Michael Kovrig and Michael Spavor with President Xi Jinping during the recent G20 summit.
Kovrig, a Canadian diplomat on leave, and Spavor, an entrepreneur, were both arrested on allegations of undermining China's national security.
Scheer also reiterated his calls for Trudeau to launch a complaint against China with the World Trade Organization and to cut Canadian funding to Beijing's Asian Infrastructure Investment Bank, to which the Liberal government has committed $256 million over five years.