Ontario Liberal Leader Kathleen Wynne says the prime minister appears to be "taking over the Conservative voice in the Ontario election."

Just hours into the Ontario election on Friday, senior federal Conservatives stepped into the fight, delivering unvarnished scorn for some of Wynne's signature policies.

In an interview on CBC Radio's The House, Finance Minister Joe Oliver broke with the convention of keeping out of provincial elections and delivered a nasty assessment of the newly released Liberal budget.

"This is the route to economic decline, not the route to economic growth or job creation," Oliver said.

He went on to challenge the Ontario Liberal promise to erase the deficit by 2017-18.

Meanwhile, Prime Minister Stephen Harper lashed out at Wynne's proposal for a provincial retirement plan, calling it an "unnecessary tax hike."

"It is interesting to me that both have jumped into the Ontario election," said Wynne on Saturday, speaking on CBC News Network.

The Liberal leader pointed out that not enough people are saving for their retirement and that 65 per cent of people in Ontario do not have a workplace pension plan, calling it a "retirement security crisis."

"There is about $60 billion of room in RSPs that's not being used and people in their 20s, 30s and 40s can't afford to put enough money aside to retire."

'We don't have a federal partner'

Wynne pointed out that Harper has declined to work with the provinces on this issue.

"If he doesn't want to help with this ... then he needs to get out of the way."

The Liberal leader went on to say that Ontario is being left out in the cold: "We don't have a federal partner."

Federal Finance Minister Joe Oliver says 'now is not the time' for Ontario's attempt to create a supplemental pension plan. (Darryll Dyck/Canadian Press)

Wynne referred to resource development in Northern Ontario's so-called Ring of Fire area, which she says needs federal involvement, which has not been forthcoming.

"In the same way that the federal government invests in the oilsands in Alberta, you might expect they would want to make an investment and work in partnership with Ontario in the Ring of Fire."

The Liberal leader went on to say her party was the only one with a "fully costed transportation plan" for the whole province.

"We are basically making investments in people," she said.

"We are proposing investments in transportation infrastructure across the whole province ... those are the kinds of initiatives, including the pension plan, that people need, that will affect people's lives every single day."

Wynne also responded to challenges from NDP Leader Andrea Horwath, who accused the Liberals of putting forth an NDP budget.

"We are not picking a fight with business, which is where Andrea Horwath would like to take us, and these are not things she has called for," said Wynne.

"She abandoned the idea of a retirement pension plan. We talked about it a number of years ago but she seemed to have forgotten about it."

Wynne defended her government, saying she has been to "every corner of the province" to listen to residents.

"They know that I'm the leader who brought in an increase to the minimum wage and who understands about working with business."

Ontario is scheduled to head to the polls on June 12.