TORONTO - There's no need for the Ontario government to hold public hearings on its plan to harmonize the provincial sales tax with the GST next July, Premier Dalton McGuinty said Wednesday, adding that voters can pass judgment on the issue in the 2011 provincial election.

"There has been, and there will continue to be, all kinds of opportunities for people to have conversations on this, whether you're talking about talk radio, letters to the editor, blogs, water cooler conversations (or) kitchen table conversations," said McGuinty.

"I would be very surprised if this was not an issue up for consideration at the time of the next election. People will have an opportunity to pass judgment on us in connection with the HST."

The opposition parties promised to use any delaying tactics they can think of to block the enabling legislation for the HST, at least until after the legislature's Christmas break on Dec. 10.

"It's going to be a long November and December for Mr. McGuinty and his Liberals if they think they're going to ram the HST legislation through without public consultations," warned Progressive Conservative critic Lisa MacLeod.

McGuinty should agree to hold public hearings on the largest tax changes in Ontario history, and hear the concerns people have about paying eight per cent more for goods and services currently exempt from the provincial sales tax, said NDP Leader Andrea Horwath.

"He needs to be talking to the people and hearing what they have to say about the fear they have about the impact of this tax," said Horwath.

The federal Conservative government gave Ontario $4.3 billion to help convince the province's Liberal government to harmonize the PST and GST, but several Tory MPs have tried to publicly distance themselves from the controversial policy.

McGuinty said he was not concerned that the federal Conservatives seem to have little interest in helping to sell voters on the 13 per cent single sales tax.

"If some people are less comfortable than others in acknowledging the role they might have played, so be it," said McGuinty.

"I just don't think that's important in the grand scheme of things."

Ontario Finance Minister Dwight Duncan was more blunt in his assessment of Conservative MPs like James Lunney, Dick Harris and Larry Miller, who have shown little enthusiasm for Ottawa's deals with Ontario and British Columbia to harmonize the sales taxes.

"The feds certainly pushed us; they've given us 4.3 billion reasons to do it," said Duncan.

"There are always rats in these debates, and it's fun to be watching those individuals who are trying to deny the $4.3 billion their government is giving us."

The split between the Ontario Progressive Conservatives -- who condemn the HST as a blatant tax grab -- and their federal cousins is making it more difficult for the provincial Tories to attack the HST.

The Canadian Press obtained a copy of an email sent by current PC Leader Tim Hudak in February, when he was still the Opposition's finance critic, which seems to suggest Hudak was not as flatly opposed to the HST as he is today.

"There are a number of models for harmonizing the PST and GST, ranging from full harmonization ... to various "made in Ontario" models that allow for certain products to remain exempt from the PST portion of the harmonized tax," wrote Hudak.

A spokeswoman for the Opposition leader said Wednesday that Hudak was simply seeking input for the party at the time and was not suggesting the PCs could support harmonization.

"I don't see anything in the email that suggests Tim ever supported the HST," said press secretary Laryssa Waler.

The federal government will have to introduce legislation in Parliament before the end of March to allow Ontario and B.C. to harmonize their sales taxes with the GST by July 1, said Duncan.