Premier Kathleen Wynne hopes that a private meeting with her NDP counterpart will provide her with a better idea of how the two parties can work together in the days ahead.

The minority Liberals need the New Democrats’ help to get their budget passed, as the Progressive Conservatives are unwilling to support it.

Since tabling their budget earlier this month, the Liberals have been putting pressure on the New Democrats to support it. And the premier has also pushed for a face to face meeting with NDP Leader Andrea Horwath, which is slated to take place on Wednesday afternoon.

On Tuesday, Horwath said that her party doesn't like the idea of adding voluntary tolls to high-occupancy highway lanes, a proposal the third party wants to see dropped from the budget.

When the Liberals tabled their budget earlier this month, they revealed plans to allow single drivers to pay to use lanes that are otherwise restricted to vehicles with two or more people inside.

Horwath told reporters Tuesday that the government must drop its plans to introduce the so-called high-occupancy toll lanes, at least until they close existing corporate tax loopholes.

"What they do is basically squeeze out people who are already carpooling for the favour of trying to get people who can pay their way into those lanes," she said. "We don't think that's the right direction to go in."

Horwath said the New Democrats can't support the budget if it adds any new tolls, fees or taxes for individuals "that the government hasn't costed" while giving corporations large tax breaks.

"We're actually using this opportunity ... to say, 'We're warning you. This is not a fair, balanced and transparent way to go, and we will not accept that kind of a plan if that's what you decide to bring in the fall," Horwath said.

Finance Minister Charles Sousa admitted Tuesday that the government does not yet know the full details about the costs and benefits of introducing the voluntary tolls.

Sousa said that it is the government’s view that the high-occupancy toll lanes are "something that we should be considering as we move forward."

However, Horwath also said she hasn't issued an ultimatum to the Liberals, who must rely on NDP support to pass the budget and avoid an election.

Horwath also said the New Democrats want to see a plan from the government to fund public transit and other infrastructure projects.

With files from The Canadian Press