Saskatchewan's Opposition is calling on the provincial government to help offset higher grocery bills by removing what the NDP is calling a "snack tax."

In 2017, the provincial government added PST to snack foods, prepared meals at grocery stores, and restaurant meals.

"We're not talking about junk food. The Sask. Party snack tax affects the staples of any good school lunch or quick family dinner," said Opposition NDP finance critic Trent Wotherspoon on at a news conference Tuesday afternoon.

"Shopping for groceries is stressful enough and folks shouldn't have to worry about PST unexpectedly popping up on their receipts. If it's food and you buy it from a grocery store, you shouldn't have to pay tax."

The NDP called the rules around what grocery items are subject to PST "convoluted," pointing out that rotisserie chickens are taxed but raw chicken is not.

During the news conference, Wotherspoon and Opposition Leader Carla Beck stood in front of a table with some items that have PST applied and others that do not.

Wotherspoon held two packages of granola bars made by the same company. A package of five is subject to PST, while a package of six is not. Some yogurt and packaged salads are subject to PST, while other yogurt products and packaged salads are not.

Beck said food should not be taxed "during a cost-of-living crisis."

"If you buy granola bars for your kids' lunches or a rotisserie chicken for a quick dinner between your kids' activities, chances are you're being charged the snack tax."

Looking at a table of grocery items, Beck said the public would not understand what is taxed and what is not and why.

"This doesn't make a lot of sense to people. I think if people looked at these two groups of food they would struggle to know which one had PST and which did not."

The NDP said the costs are also being impacted by "shrinkflation," where food items are being packaged in smaller sizes while prices remain similar or higher.

Finance minister says she would like to lower the PST

Provincial Minister of Finance Donna Harpauer said the government added the PST in 2017 to certain grocery items that were also subject to the GST and what the federal government defined as "snacks."

She said she was not sure what rationale the federal government used, but said the province applied the same rules due to "clarity for the retailer."

"The vast majority of groceries are tax-free," Harpauer said in the assembly Tuesday in response to a question from Wotherspoon.

Harpauer told reporters the government was not planning to remove the so-called "snack tax."

"We made a difficult decision in 2017. We experienced years when resource revenue was down and we needed to find ways to generate revenues so we could continue with increases for education, health care and social safety nets."

Harpauer said that in the past resource revenues paid for as much as 32 per cent of government expenses and that in this year's budget that number has dropped to 12.5 per cent.

She said increasing and broadening the PST in the past has added stability and predictability to provincial revenues.

When asked about lowering the PST from six per cent, Harpauer said the government does not have a position but added, "I would like to lower PST period."