TORONTO - Ontario's New Democrats say they will remove the provincial portion of the harmonized sales tax on gasoline if elected this fall.

Leader Andrea Horwath says her party can't cut the eight per cent portion overnight, but will work to make life more affordable one step at the time.

She says her plan would reduce the tax on gasoline by one per cent every year.

To pay for the plan, which will cost $500 million, the NDP will shift some of the tax burden back to businesses.

Horwath didn't explain how businesses would pay for her plan as she opened a pre-campaign convention today. She says more details will come when she unveils her platform Saturday.

The NDP has already promised to cap gasoline prices and remove the province's chunk of the HST from home heating and hydro bills.

The party also says it will stop fare hikes for public transit by subsidizing the system across the province, remove ambulance fees for people who need to be transported to hospital, and raise corporate taxes.