Officials in Toronto have outlined the areas in the heart of the city that will be restricted to pedestrian and vehicular traffic as a result of the G20 summit.

Authorities offered details Friday of the security measures they are going to enact in advance of the meeting of world leaders, which is due to take place between June 26-27 at the Metro Toronto Convention Centre.

The construction of a security fence will begin on June 7 and will continue 24 hours a day until it is completed, Supt. Tom Russell, the head of G20 planning for Toronto police, told reporters at a news conference. People will have to pass through checkpoints to get through.

"We know this will be inconvenient to Torontonians and we ask for your patience and understanding during this time," he said.

"It is our hope that members of the public will be able to move freely throughout the fence perimeter until the evening of Friday, June 25."

The northern portion of the fence will run along Wellington Street West, while the southern portion will run along Lakeshore Boulevard West.

The western portion zigzags southwards along Windsor Street and Blue Jays Way. The eastern portion runs along Bay Street, east along Front Street West and then south on York Street. Union Station, the Air Canada Centre and the Rogers Centre are outside the security fence.

The boundaries of that fence are subject to change, however, Russell said, "and will be communicated to the public as soon as possible."

Outer zone restricted to traffic

Traffic, meanwhile, will be restricted from Yonge Street west to Spadina and King Street West south to Queen's Quay.

That area will not be bound by a fence, rather, "it is the point where vehicle traffic will engage with the Toronto police officer," said Russell.

Restrictions around the downtown core will tighten significantly from the evening of June 25 to June 27. Some of the more significant restrictions during that time include:

• The closure of all exits to Front Street at Union Station.
• All sections of the underground PATH system will be closed.
• Heightened parking enforcement in the outer security perimeter.

Throughout the G20 weekend, there will be restrictions on Lakeshore Boulevard, as well as the Gardiner Expressway and Highway 427, said Russell.

"Members of the public can expect significant traffic disruptions in the downtown area," he said.

Authorities have outlined the security zones that will be enacted leading up to the G20 summit in downtown Toronto.