TORONTO - Two maverick Progressive Conservatives refused to leave the Ontario legislature Monday -- and were prepared to stay the night -- over the government's refusal to hold provincewide public consultations on tax harmonization.

A compromised aimed at avoiding a long standoff appeared to materialize late Monday, but it wasn't immediately clear whether it was enough for the Tories to abandon their sit-in.

The tentative deal involves extending public hearings on the HST bill from one day to 2 1/2 days in Toronto, which would push them into next week, said NDP House Leader Gilles Bisson.

The governing Liberals plan to ram through legislation that will allow it to merge the eight per cent provincial sales tax with the five per cent federal GST by Thursday of next week, and there's little that can be done to delay it, he said.

"The government, quite frankly, could do what it wants and there's not a hell of a lot we can do," Bisson said.

"We could hang from the chandeliers, we can spit nails, we could ring bells, we can pump our desks, we can get thrown out. At the end of the day, it's not going to make a heck of a difference because the rules are fairly clear."

But Randy Hillier, one of the Tories who refuses to leave the legislature, said he was preparing to hunker down for the night with his colleague Bill Murdoch.

"There's no deal yet, so we're staying until there's a deal," he said, adding that he's prepared to stay all week if need be.

David Spencer, a spokesman for Liberal House Leader Monique Smith, said there's not final agreement yet, but all three parties will meet again Tuesday morning to see if they can hammer one out.

The protest began Monday afternoon when Murdoch called Premier Dalton McGuinty a liar for "shutting down" public hearings.

"Where I come from, we call that a cop-out," he told the legislature. "Where I come from, Dalton McGuinty is a liar."

He refused to retract the remark -- a big no-no in the legislature -- and was asked to leave. But Murdoch wouldn't budge.

Other Tories flocked to their colleague's side to block any attempt to remove him, then repeatedly drowned out debate by pounding their desks and shouting, "Call public hearings!"

After several warnings, Speaker Steve Peters suspended both Murdoch and Hillier -- who helped form the human shield around Murdoch -- until the end of the legislative session.

If the two set foot outside the legislature -- even for a quick bathroom break or a bite to eat -- they won't be able to return until a new session starts with a speech from the throne, which would deprive the 25-member Tory caucus of two votes.

Both Hillier and Murdoch are prepared to stay all night in the legislature if that's what it takes to twist the government's arm, said Opposition House Leader Bob Runciman.

"They're camping out, if you will, for the whole evening," he said. "So until we get this resolved in a way that's acceptable to our caucus, then we intend to remain in the legislature."

The governing Liberals have only granted the public about five hours during a legislative committee hearing on Thursday to talk about the HST, which isn't nearly enough time, he added.

"We're looking for expanded public hearings, preferably in communities outside Toronto," he said.

"But I think it's clear they're closing off debate here, they're limiting the public hearings to about five hours in Toronto, and we know that there are hundreds, if not thousands of people who want to appear before the committee."

The Liberals, who hold a 72-seat majority in the legislature, insist that the Opposition stunt won't hold up the HST legislation.

"I think their childish behaviour is a negative reflection on their party," said Smith.

"But I think that we continue with business as usual. We're trying to get our work done."

The stunt marked an escalation in Tory protest tactics over the HST, which they have labelled as one of the biggest tax grabs in the province's history. Only this time, they took a page from the Liberal playbook.

The protest is similar to the one mounted by Liberals in 1995, when Alvin Curling refused to give up his seat and staged a sit-in to protest a massive Conservative government bill, Runciman said.

Unlike traditional delaying tactics, it required members to break the rules, but won the opposition party three more weeks of public hearings.

Both the Liberals and NDP formed a human shield around Curling, who stayed overnight in the chamber and was forced to relieve himself, according to some political veterans, in a bottle hidden under a blanket on his lap.

That prospect doesn't seem to have deterred Murdoch and Hillier, who are well known for their outspoken ways and propensity to thumb their noses at authority.

"My resolve is unshakable, same with Bill," said Hillier.

"We're expecting the Liberals to do the right thing and hold those public hearings. And as you know, we know how to be disruptive if we have to."

Asked whether he was prepared for the indignities that a sit-in may entail, Hiller turned coy.

"We're a very resourceful lot," he said with a laugh.

"I went to Scouts when I was a youngster and our motto was, 'Be Prepared."'

Murdoch was once booted out of caucus for suggesting that former Conservative leader John Tory find another job, while Hillier has been ejected from the legislature before for calling the Liberals liars and refusing to retract the remark.