Here's an article from the Toronto Star back in November 2009, just before Toronto was designated as the G20 summit city:
"Toronto would be ready to host the G20 summit of world leaders if Ottawa chooses to move the meeting here, says Mayor David Miller. Speculation has grown this week that the event will be moved here from Huntsville, because the rural Ontario town cannot handle the security and hotel needs of the delegations. Even though such a gathering would bring heightened security, road closings and possibly large groups of protesters, Miller said Toronto would be able to handle it. "We're not going to turn into an armed fortress," he said Friday. Toronto is a major conference-hosting city that has just opened the new Allstream Centre at Exhibition Place meant to hold meetings of this scale, he said. "If the G20 is here, we will be known all around the world. We are a place that can host the world because we have the world here," he added."
It certainly sounds like it was a package deal - Ottawa and the city were both behind it.
Thank God for cached pages on the internet.
http://viableopposition.blogspot.com/