Reforms to the parliamentary pension plan are expected to be included in a second omnibus budget implementation bill to be introduced shortly.
But if the bill is hundreds of pages long and includes an array of controversial measures — like the first budget bill last spring — New Democrats and Liberals would have little choice but to vote against it.
And they suspect that's the whole point.
They believe the pension reforms will be stuffed into an unpalatable budget bill precisely so that Conservatives can accuse opposition MPs of refusing to share the pain of Canadians, whose retirement savings have taken a big hit over the past few years and who are being asked to wait until 67 to collect old age security.
Liberal House leader Marc Garneau says his party will support any and all measures to trim MPs' pensions and he's challenging the government to produce a separate bill so that MPs can have a clear vote on the matter without other issues intruding.
"If Canadians need to suck it up, so do we. Liberals are ready for it," Garneau told the Commons on Wednesday.
"I challenge the prime minister to commit today to that reform in the form of a single, stand-alone bill that is not mixed in with other bills ... so that Liberals can unequivocally vote for it."
Treasury Board president Tony Clement ignored the challenge as he thanked Garneau for his "exuberance" on pension reform. Clement suggested the one-time astronaut and potential Liberal leadership contender "must be ready for takeoff on some project of his own."
A committee of Conservative backbenchers is crafting the pensions reforms, which are expected to include boosting MPs' contribution rate to 50 per cent from 14 per cent and raising the age of eligibility to 65 from 55.
Unlike the Liberals who've signalled their intention to support whatever the Tories come up with, sight unseen, New Democrats are taking more of a wait-and-see approach.
NDP Leader Tom Mulcair said his party is "more than willing" to reform the pension plan but it should be done by an independent, blue-ribbon panel rather than by MPs, who are in an obvious conflict of interest.
"We'll see what they do. If it's something that's objective and a bit at arm's length, we know that they're not playing a game with it," Mulcair said.
"And if they try to embed it in a 700-page bill that's doing a whole bunch of other things that they know darn well that we'll never be able to vote for, we'll know that it's about a political game again for the Conservatives."
At the same time the government is preparing to scale back parliamentary pensions, the cap on MPs' salaries, which have been frozen since 2010, is set to be lifted in 2013-14.
Mulcair said that issue too should be decided by an independent panel of experts.
However, deputy Liberal leader Ralph Goodale said any increase in MPs' salaries would be inappropriate.
"As long as the international circumstances remain as difficult as they are, as long as public servants are being laid off and old age pensions are being cut back, all of the other austerity measures coming into effect, it would seem to me a pretty hard sell that members of Parliament should see an increase in their salaries."
Also on HuffPost