TORONTO - A giant transformer was moved onto the site of a cancelled gas generating station in Mississauga on Monday, just days after the Ontario government was hit with a $300-million lawsuit for breach of contract.

Construction on the controversial natural gas plant was finally halted late last November, almost two months after Premier Dalton McGuinty announced the project was being cancelled in the middle of the provincial election campaign.

The transformer, more than two-stories high, was delivered to the site on a huge flatbed trailer after crews lifted hydro wires so it could safely pass underneath.

The Ministry of Energy confirms delivery of the electrical transformer, but says it will only to be stored on the site.

A ministry spokeswoman says construction has not resumed at the gas plant, which the Liberals have promised to move to another location.

Earlier Monday, McGuinty came under attack during question period over the lawsuit filed last week by a Washington, D.C.-based investment fund against the Ontario Power Authority and the government for cancelling the 280-megawatt plant in Mississauga.

Both the Conservatives and NDP said the Liberals cancelled the gas plant solely to save government seats in the election and not because of power needs or energy policy.

"Why can't the Premier give the public a sense of how much their last-ditch Liberal seat-saver decision is going to cost," asked New Democrat energy critic Peter Tabuns.

"How much more, Premier, will your decision cost the public?"

The Tories also lashed out at the Liberals for cancelling the Mississauga gas plant in mid-campaign, and for cancelling another one in nearby Oakville, in another Liberal-held riding, the year before.

"First you cancelled the Oakville power plant for purely political reasons, then, in the midst of the election, you cancelled the Mississauga power plant in what was widely viewed as a seat-saver program," said Opposition energy critic Vic Fedeli.

"Will you now come clean with the Ontario taxpayers and tell us the true cost of cancelling these projects."

Energy Minister Chris Bentley vowed to "vigorously defend" the lawsuit by EIG Management, the American financing company behind the Mississauga plant, and said the province was still working with the developer in an effort to find another location for the natural gas power station.

"The Ontario Power Authority and Greenfield are continuing to have discussions about the relocation of this particular plant," he said.

However, the Conservatives predicted more costly legal troubles to come for the Liberals, and taxpayers, from the two cancelled energy projects.

"As this is likely the first in a long series of lawsuits that we can expect, isn't this lawsuit proof positive that your decision had nothing to do with our energy needs, but only satisfied the Liberals' political needs," asked Fedeli.

Bentley fired back that the Tories said they too would cancel the Mississauga gas plant during the election campaign.

"It's funny how the mind seems to drift in a few months, because during the election they didn't want to build it. They supported our decision," said Bentley. "Now, we get a little wiggle and a waffle. We're not really sure now."