The proposed merger between the Canadian Alliance and the Progressive Conservative Party has hit another snag. A group of prominent Tories is demanding a full national convention to debate the union.

An open letter signed by a number of well-known Tories, including former party leader and prime minister Joe Clark, said the process "to extinguish the Progressive Conservative Party and be assimilated into another party is not only unethical and unconstitutional, it is fundamentally undemocratic."

That's why the group, led by MPs John Herron and Rick Borotsik, former Newfoundland premier Brian Peckford and former MPs Dorothy Dobbie and Joe Hueglin, is demanding a full national meeting.

"Obviously there's a Yes faction,'' supporting the merger plan, said Borotsik. "Our position as the No faction, if you will, is: let's make it a truly transparent process."

The PC management committee decided two weeks ago to create a "virtual convention'' to ratify the proposal. The committee agreed that delegates from 20 regional hubs will vote on the proposed merger by teleconference on Dec. 6.

The Tory constitution requires a two-thirds majority to ratify the merger, disband the existing PC party and create a new Conservative Party of Canada.

Tory leader Peter MacKay has faced harsh criticism from his party since mid-October, when he and Alliance leader Stephen Harper unveiled the deal. He insists everyone will get a chance to debate and vote on the proposal.

"It could not be more democratic," he says.

Chief among his critics is David Orchard, whose support at the Tory convention ensured MacKay's win. In exchange, MacKay promised not to engage in merger talks with the Alliance.

Orchard is not alone in his opposition. Senators Lowell Murray, Mira Spivak and Norm Atkins, former cabinet ministers Flora MacDonald, Heward Grafftey and Sinclair Stevens are among the more than 100 names affixed to the letter.

While many are opposed to the merger, several prominent Tories think it's a good idea.

A full-page ad that appeared over the weekend in The Globe and Mail included the names of former prime minister Brian Mulroney, former Ontario premier Ernie Eves and four of the five provincial Tory premiers.

The only Tory government head not lending his name to the ad is Danny Williams, the premier-designate of Newfoundland and Labrador.