THUNDER BAY, Ont. -- Ontario Premier Kathleen Wynne vowed to go ahead and spend $1 billion over the next decade to build a transportation route to the mineral-rich Ring of Fire in the province's north -- with or without financial help from the federal Conservatives -- if the Liberals are re-elected on June 12.

Prime Minister Stephen Harper has shown no interest in helping the province develop the massive chromite deposit, which would be a big boon to Ontario's economy and create jobs in hard-hit northern communities, Wynne said Sunday in Thunder Bay, Ont.

"We have not seen that kind of responsibility taken," the Liberal leader told supporters at the party's platform launch.

"He has not taken that responsibility, but I am. We are making it a priority for my government."

But officials said they haven't decided where or when they'll start building the route, or how they'll find another $1 billion to complete it in a remote region of northern Ontario if Ottawa won't provide the funds.

Those decisions will be up to a development corporation that Wynne said she'd create within 60 days of taking office that will include both levels of government, First Nations and private companies.

Much of the platform Wynne detailed on Sunday essentially fleshed out unannounced details of the spending plans outlined in the Liberals' May 1 budget, which both opposition parties rejected -- triggering an election. Wynne said she'd re-introduce the fiscal plan if the Liberals win.

The $119.4-billion budget had promised to put up $1 billion for infrastructure to develop the Ring of Fire, but only if the federal Tories matched the funds. That condition now appears to have changed.

"We have not seen any indication in the last number of weeks that Stephen Harper is interested in stepping forward and making the same kind of support available to the Ring of Fire as he made available to the oilsands," Wynne said.

The Liberals are also pledging to fund 20 more hospices, cap or cut hospital parking fees for frequent visitors and patients, and provide more resources to help high-school students plan their path to a desired career, including revamping the curriculum for the mandatory Grade 10 careers class.

Their platform finds common ground with certain promises the Progressive Conservatives and New Democrats have made in their visions for the province as well.

The Liberals say they'd work to extend physical activity for students to an hour a day, as well as improve their math scores by reviewing the curriculum, helping teachers specialize in teaching math and providing more help for students who are struggling. They also say they'd increase apprenticeship spaces, which the Progressive Conservatives have proposed.

On the health care front, the Liberals are promising to continue to reduce wait times by focusing on referrals to specialists and guarantee that every resident will have access to a primary care provider, such as doctors, nurse-practitioners and family health teams. The New Democrats have also said they'll reduce wait times and provide more access to health-care services if they're elected.

Wynne, some union leaders and disgruntled New Democrat supporters have slammed NDP Leader Andrea Horwath for refusing to support the last budget, saying she could have supported many of the measures it contained.

Those included a hike in the minimum wage, $29 billion over 10 years to improve transit infrastructure -- including the Ring of Fire --and pay hikes for personal support workers and early childhood educators.

The budget, which projected a $12.5-billion deficit this year, also promised a provincial pension plan and earmarked $2.5 billion for corporate grants in an effort to attract investment and keep businesses in Ontario.

The NDP was quick to criticize the Liberal plan Sunday.

New Democrat John Vanthof said the Liberals are desperate and trying to "up the ante" with their platform to make their budget promises sound more attractive.

They've made plenty of promises about the Ring of Fire that they've failed to deliver, he said. The development corporation tasked with helping to handle the project was announced last November and still isn't up and running.

"Now they're 'oh, we promise you this time we'll actually do it this time,"' said Vanthof, who is running for re-election in the northern riding of Timiskaming-Cochrane.

"Northerners are to the point where we just don't believe them anymore. And that's why we let the budget drop."

The NDP platform also promises to develop the Ring of Fire, but doesn't allocate any money for it over the next four years.

Wynne and Horwath are expected to face off Monday in a debate on northern Ontario issues, but Progressive Conservative Leader Tim Hudak said he can't make it.

In the 2011 election, Wynne's predecessor Dalton McGuinty didn't participate, citing a scheduling conflict.

"I'm telling you that it would never occur to me not to take part in the northern debate," Wynne said.

Wynne also said she can still come through on her promises while still balancing the budget in 2017-18, but she said she won't cut public services to meet the deadline.

The budget projects Ontario's net debt to grow by $20.1 billion to $289.3 billion this year, a staggering 40 per cent of gross domestic product.

One bank economist noted that Ontario's current ratio of nearly 39 per cent creates a "longer-term vulnerability" for the province.

Moody's Investments Service said the planned increase in deficits for 2014-15 and 2015-16 compared to previous budget estimates "represents a credit negative for the province."