Canada’s retaliatory tariffs on American goods officially kicked in Sunday, marking a new milestone in the ongoing trade dispute between the two countries.

The list of $16.6 billion worth of tariffs on U.S. goods includes a 25 per cent surtax on more than 100 steel and aluminum products and at 10 per cent surtax on more than 70 other goods, including chocolate, pizza and maple syrup, to name a few.

Canadian Prime Minister Justin Trudeau is skipping the Canada Day party on Parliament Hill and will instead be making two stops in towns at the forefront of the burgeoning trade dispute: a steel refinery in Regina, and a food processing plant in Leamington, Ont.

In his Canada Day message, Trudeau paid tribute to the working-class Canadians who will be impacted by Canada-U.S. tariffs.

"Canada's workers build the roads and bridges that get us to work on time and back home again,” Trudeau stated in his address.

"From Ontario steel to Quebec aluminum, from agriculture and the energy sector in the Prairies and the North, to forestry in British Columbia and fisheries in the Atlantic, Canadians get the job done - and build our communities along the way.”

The tariffs are an equal response to 25 per cent steel tariffs and 10 per cent aluminum tariffs that the U.S. government instituted on June 1. They will remain in place until the U.S. tariffs are lifted.

Jerry Dias, Unifor’s national president, called Canada’s retaliatory tariffs a “necessary evil.”

“Donald Trump has declared war on Canada and we have absolutely no choice but to retaliate,” he told CTV News Channel. “Corporations, as well as our members, don’t know what the next move is because we’re convinced that Donald Trump doesn’t know what his next move is either.”

Ken Neumann, national director of United Steelworkers Canada, said the tariffs are a step in the “right direction.”

“It shows the U.S. government that we’re not going to be pushed back,” he said. “We’ve got nothing to be ashamed about.”

The Canadian tariffs are expected to hit industries in many of the swing states that are crucial for Republicans in the midterm elections, including Pennsylvania, Ohio, Kentucky and Florida.

Bruce Heyman, former U.S. ambassador to Canada, thinks the Canadian tariffs will get things moving toward reconciliation between the countries.

“Clearly, I think after today, the ball’s going to be in the U.S. court and they’ll just have several choices of paths they want to take and I’m hopeful the messages today are one’s that indicate a constructive path,” he said.

Heyman thinks U.S. President Donald Trump has three options when it comes to next steps: he can either scale the escalating trade tensions back, he can stabilize the situation and get back to the NAFTA negotiating table or he could escalate things further.

“Canadians and-- I’m telling you-- Americans alike, don’t want to see tariff escalation,” he said.

Trudeau and Trump spoke over the phone on June 29 where they talked about trade and several other topics. Trudeau reiterated that he “had no choice” but to announce retaliatory tariffs, according to the prime minister’s office.

The two agreed to keep in contact moving forward.