Canada Post and the union representing its workers remain far apart in negotiations for a new contract, with a work stoppage looming on July 2.

Thursday marks the last day that Canadians can expect to receive mail in a timely manner, with a statutory holiday on Friday and a possible work stoppage coming on Saturday. Canada Post has already warned businesses and members of the public to make alternate arrangements for necessary correspondence by mail, ahead of the deadline. The last day to send mail and ensure it is delivered on-time was Wednesday.

However, the Canada Revenue Agency says that Old Age Security and CPP cheques, along with those for the Working Income Tax Benefit and the Canada Child Benefit, are deemed "essential" and will be delivered even during a labour disruption.

Canada Post says its latest offer to the union was tabled on Saturday, but the union has yet to formally respond. Meanwhile, the Canadian Union of Postal Workers says its own request to delay a work stoppage with a two-week "cooling off period" has been declined.

The union has released a list of 24 demands in its negotiations with Canada Post, but the main sticking point is pensions for future employees.

"The number one issue for us is the pension," Canada Post spokesperson Jon Hamilton told CTV News Channel. "We face a $6-billion pension solvency deficit."

Canada Post has offered to leave the existing employees' defined benefit pension plans untouched, while introducing a defined contribution pension plan for new hires. Essentially, existing employees' pensions would continue to be managed by a pension fund, while new hires would have to allocate their pension contributions themselves.

"If you're an existing employee, you don't lose anything, but we certainly can't add anything," Hamilton said. "We can't keep adding new employees to the defined benefit pension plan, but we can secure the pension plan for those people that are in it."

The union has suggested that Canada Post is trying to create a two-tiered system among its 50,000 employees. The union also points out that Canada Post has been turning a profit for years, and made $44 million in the first quarter of the year. Postal workers have been without a contract since late 2015.

"We don't see any justification for the cuts they're putting forward," Mike Palecek, a spokesperson for the union, told CTV News Channel on Thursday. "Canada Post is fully capable of paying its employees now, and there's no reason they shouldn’t be able to do the same for future employees."

Palecek says the union does not want a strike, but Canada Post seems prepared for a work stoppage. "We're quite concerned that Canada Post is trying to provoke a labour dispute," he said.

The union is also calling for Canada Post to restore door-to-door mail service for all neighbourhoods where community mailboxes were recently installed.

The last Canada Post labour disruption occurred in 2011 with ten days of rotating strikes followed by a lockout. Ottawa eventually invoked back-to-work legislation – something that the Liberal government says it won’t do this time around.

With files from The Canadian Press