TORONTO -- Ontario is proposing changes to the Greater Golden Horseshoe's growth plan that the government says would make it easier and faster to build housing.

The government says the changes would come while maintaining protections for the Greenbelt, an area designated to keep environmentally sensitive land from urban development.

Critics have suggested the Progressive Conservative government wants to open the door to Greenbelt development, but it has denied that charge.

Premier Doug Ford generated controversy during last year's election campaign when he initially pledged to open parts of the area to build housing -- a promise he backtracked on after facing intense criticism.

But the NDP and the Green party accuse the government of putting Greenbelt protections at risk through omnibus legislation introduced late last year aimed at cutting red tape.

Proposed changes to the growth plan that the government announced Tuesday include some eased density targets.

The previous targets, introduced by the former Liberal government as anti-sprawl measures, had been blamed by some critics for a housing supply shortage in the Toronto area.

The Liberal plan said that any future projects on undeveloped land would have to accommodate more people and jobs -- a minimum of 80 per hectare -- with higher density targets around GO Transit and subway stations, light rail and bus rapid transit.

The new plan proposes to lower that target from 80 to 40, 50 or 60 in various regions outside Toronto.

The changes would better allow municipalities to address local needs, Municipal Affairs and Housing Minister Steve Clark said in a statement.

"We believe there are too many barriers standing in the way of creating housing and attracting investment in the region," he said.

The Greens accused the government of forcing an unnecessary choice between building homes and protecting green space.

"The premier's actions won't solve the housing affordability crisis. But it will grease the wheels for land speculators to profit," Leader Mike Schreiner said in a statement. "Farmers feed cities, and they need farmland to grow the crops that sustain us."

The advocacy group Environmental Defence described the proposed changes as further evidence that the government is bowing to pressure from developers

"What the region needs are more housing options for renters and owners, within our cities, close to where people want to live, work and play. Not sprawling subdivisions on farmland, forests and the source of our drinking water," the group's executive director, Tim Gray, said in a statement.

The government says the current vacancy rate in Toronto is close to one per cent, and two to three per cent is generally considered to represent a balanced rental market.

The growth plan is mean to accommodate the growing population in the Greater Golden Horseshoe, which is expected to reach 13.5 million by 2041, an increase of four million people.

Members of the public have 45 days to comment on the proposals on the province's regulatory and environmental registries.