MONTREAL -- Hundreds of unionized postal workers and their supporters marched to Prime Minister Justin Trudeau's Montreal office on Saturday hoping to push forward negotiations with Canada Post.

An official with the Canadian Union of Postal Workers said talks with the Crown corporation remain stalled on key issues such as pensions and wage parity.

"It's still in discussion, but the files aren't moving forward," Sylvain Lapointe said. "The big issues are still on the table."

The union members said the event's goal was to call on the Liberal government to pressure Canada Post to negotiate in good faith with its workers.

The union's national president said Canada's Post's positions runs counter to the values promoted by the Liberal party.

"We have a government that's advocated for better pensions for everyone and made that a major part of their mandate, but here we have a Crown corporation which is going the opposite direction, trying to take secure pensions away from future generations," Mike Palecek said.

Canada Post has said it wants to change its pension plan to bring it in line with the private sector. It wants new employees to be covered under a defined contribution plan instead of a defined benefit plan, which reduces costs for companies and shifts the risk for future payouts to employees, who are no longer guaranteed a set payment in retirement.

The union wants changes in how rural and suburban mail carriers are paid. They want to be paid by the hour, like urban letter carriers, not by how many packages they deliver.

Palecek said the suburban carriers, who are 70 per cent women, end up making 28 per cent less than their predominantly male urban counterparts.

"We have a prime minister that has been advocating for pay equity, but yet the most glaring case of pay equity left in the federal public sector -- here of the rural and suburban mail carriers of Canada Post -- remains completely unresolved," he said.

Most of the protesters were from the Montreal area but others were bussed in from Ottawa and Quebec City.

Many came dressed in Canada Post uniforms and waved signs saying "save Canada Post," and "Because it's 2016," referring to a remark Trudeau made late last year when unveiling his gender-balanced cabinet.

The two sides have been negotiating since late 2015.

Canada Post withdrew a threat to lock out its workers in early July, saying it wanted to allow both parties to focus on negotiations.

Mail carrier Alice Picard, who brought her two young daughters to the event, said she's hoping for a quick settlement.

"Threat of lockouts are hard on morale," she said. "It's worrying, it has to move forward. I need my salary to pay rent and feed my family."