Michael Ignatieff says federal Liberals will support legislation to implement a harmonized sales tax in Ontario and British Columbia, despite previously bashing it as a job-killing "Harper sales tax."

The Liberal leader announced his decision Tuesday after meeting his MPs, many of whom felt trapped in no-win situation and were torn over what to do.

Some MPs fear a backlash from voters in the two provinces, who are becoming increasingly angry about the prospect of paying more for a host of goods and services.

Others fear alienating the Liberal governments in Toronto and Victoria, whose campaign machines will be vital to the success of federal Liberals in the next election.

In the end, Ignatieff came down on the side of respecting the wishes of provincial governments, not to mention longstanding federal Liberal policy.

"This is a request from the provinces because they believe it'll improve the competitiveness of their economy and create jobs," Ignatieff said, noting that federal Liberals have promoted harmonization for 15 years.

"We will support this legislation in Parliament."

Just last summer, during a tour of B.C., Ignatieff criticized Prime Minister Stephen Harper for pushing provinces in the midst of a recession to adopt what he derisively referred to as the "Harper sales tax."

In September, he demanded a clarification after Ontario Premier Dalton McGuinty said Ignatieff had promised he'd abide by a federal agreement to ease the transition to the HST with $4.3 billion for Ontario and $1.6 billion for B.C.

After a week of confusion, Ignatieff grudgingly acknowledged that he would, in fact, honour that agreement should he become prime minister.

By Tuesday, that acknowledgment had become a point of principle which Ignatieff maintained demonstrates the difference between him and Harper, whom he slammed for tearing up federal-provincial agreements on child care and aboriginals upon taking office.

"We're practising a federalism of respect. Mr. Harper . . . practised a federalism of disrespect and division and I don't think that's any way to run a federation."

Ignatieff also slammed Harper, who'll be in China when the HST implementation legislation is introduced, for trying to distance himself from the unpopular tax and "pretend he has nothing to do with it."

"This was initiated by Mr. Harper and leadership means taking responsibility for your decisions. I've done so today. I wonder why he has not."

The Bloc Quebecois is also likely to support the legislation, leaving only the NDP to vote against it. NDP Leader Jack Layton is hoping to parlay consumer anger over the tax into votes for his party.

"The Liberals have decided to turn their backs on the hardworking families who are going to have to pay now billions of dollars in more taxes," Layton said Tuesday, vowing to use every procedural tool available to stop the legislation.

Ignatieff said the vote on the HST implementing legislation will be "whipped," meaning all Liberal MPs will be expected to support it.

That may yet prove difficult for some.

Victoria MP Keith Martin continued Tuesday to crusade against the HST in his province, predicting it will kill jobs, hurt people of modest means, and cramp the economy. He dismissed his leader's argument that federal politicians should respect the wishes of provincial governments.

"We simply are not there to be lackeys, to just move ahead and nod our heads and say yes," Martin said. "Our role and responsibility is to defend the interests of the people in our province."

Toronto MP Judy Sgro acknowledged that federal Liberals are worried they'll be blamed for the HST by Ontario voters, who'll likely cast ballots federally before they vote in a provincial election.

She said history shows voters take out their anger on the first politicians to show up at the door.

"Clearly, this is a difficult issue," she said.