Ontario has joined Quebec and Nova Scotia in warning Prime Minister Stephen Harper to abandon his plans to reform the Senate.

In fact, Ontario and Nova Scotia say instead of changing the Senate to set term limits and allow for elections, the upper chamber should be closed forever.

"Ontario's position on Senate reform: abolish the Senate," Premier Dalton McGuinty said via his Twitter feed Tuesday morning.

Harper is expected to move quickly to introduce two separate Senate reform bills — one to impose term limits on senators and the other to allow provinces to elect nominees whom Harper would then appoint to the Senate.

However, McGuinty said he's spoken with other premiers and believes the best option is to simply get rid of the Senate altogether.

"We think the simplest thing to do is abolish it, and I think, frankly, to reform it in any substantive way is just not possible," McGuinty said after touring a Chrysler factory in Brampton, Ont. "Based on my discussions with other premiers, based on the formula that's in place in order to ensure that there is reform, it's not going to happen."

Ontario has almost 40 per cent of Canada's population but less than 25 per cent of seats in the Senate, McGuinty pointed out.

"We have one elected, accountable body that sits in Ottawa for us in the House of Commons," he said. "I just don't think we need a second, unelected, unaccountable body."

On Monday, Quebec Intergovernmental Affairs Minister Pierre Moreau said that the federal government alone cannot reform the Senate, adding it must be done through a constitutional amendment, approved by at least seven provinces.

Also Monday, Nova Scotia Premier Darrell Dexter, who like McGuinty believes the Senate is "not necessary," said the federal government should not arbitrarily make changes to the upper chamber without first consulting the provinces.

Harper's previous attempts to pass the Senate reform bills were thwarted by the opposition parties. However, the Conservatives now have majorities in both the House of Commons and the Senate thanks to the May 2 election and the prime minister's move to name three defeated Tory candidates as senators.

Ontario NDP agree with Liberals

Ontario's New Democrats welcomed McGuinty's call.

"It's interesting that the McGuinty Liberals are finally saying what New Democrats have been saying for a long time, which is it's time to abolish the Senate," said Leader Andrea Horwath. "Let's face it, the senators are a bunch of Liberals and Conservatives that are sitting around for lots and lots of money and not doing very much and we really do need to get rid of that upper chamber."

However, the Progressive Conservatives, who lead the public opinion polls with an Ontario election just over four months away, said the reality is Canada has a Senate, and senators should be elected, not appointed.

"The premier's position is simply a dodge. He wants to avoid the question," said Opposition Leader Tim Hudak. "The Senate's not going to be abolished, I don't see the provinces agreeing to that, so as long as we do have a Senate, I believe that Ontario should directly elect its senators."

Moreau said Quebec was not objecting to modernizing the Senate, but has held the same position that any changes should go through a constitutional amendment for more than 20 years.

In the past, Newfoundland and New Brunswick have also objected to the federal government proceeding unilaterally with Senate reform.