Quebec's newly elected separatist government accused Canadian Prime Minister Mark Carney on Tuesday of sidelining the province ahead of a major European Union summit in Montreal, escalating tensions between the federal government and Quebec's independence movement. President Donald Trump also congratulated Quebec Premier Paul St-Pierre Plamondon following his party's election victory, adding another political dimension to the dispute.

Quebec Justice Minister Marie-Claude Sarrazin said Ottawa rejected St-Pierre Plamondon's request to address the summit, which opens Thursday. The gathering will bring together Carney, European Commission President Ursula von der Leyen and European Council President António Costa to discuss expanding trade and investment ties.

St-Pierre Plamondon called the decision a "serious lack of respect" in a post on X, accusing federal officials of preferring that he "serve shrimp cocktail" rather than participate in the discussions. Carney disputed that characterization, saying the premier had declined an invitation to attend Thursday's dinner with European leaders.

"It's his decision to leave an empty chair again," Carney told reporters in French.

The summit is expected to address digital trade arrangements and European Investment Bank financing for Canadian critical minerals projects. Quebec's government has raised concerns that Ottawa could negotiate agreements affecting areas of provincial authority without giving the province a meaningful role.

"The federal government has chosen to prevent Quebec from having a say on its own territory," Sarrazin said, warning that Quebec would insist on its authority over matters within its jurisdiction.

Trump weighed in Tuesday, congratulating St-Pierre Plamondon in a Truth Social post and sharing an article portraying the separatist party's victory as a setback for Carney. The Parti Québécois won 60 of the 127 seats in Quebec's National Assembly in the October 5 election, leaving it four seats short of a majority.

St-Pierre Plamondon has promised to pursue another referendum on Quebec independence, although he has said the vote would not take place until after Trump leaves office. The separatist leader's dispute with Ottawa comes as Canada faces mounting pressure from Washington over trade.

Trump accused Canada on Monday of charging the United States "massive tariffs" and treating the country badly during remarks in Mississippi. Trade negotiations between Washington and Ottawa collapsed in August, but White House economic adviser Kevin Hassett said Sunday that discussions had "picked up" and were "gathering steam." The Trump administration has also recently exempted certain Canadian imports from 50% tariffs following pressure from Sen. Susan Collins, a Maine Republican.

Carney maintained that Quebec had been consulted during preparations for the European summit, saying federal officials had held three discussions with provincial representatives. Despite the public dispute, Quebec's delegate general in Brussels, Hélène Drainville, said officials from both governments were cooperating on the proposed agreements.

"Right now, all the signals are green," Drainville said, while emphasizing that Quebec "has to be at the table" when negotiations involve provincial responsibilities. The disagreement nevertheless highlights the competing pressures facing Carney as he pursues closer European economic ties while managing trade tensions with Trump and a renewed independence movement in Quebec.