By Steve Rennie, The Canadian Press

OTTAWA - The federal Liberals are calling for an emergency swine-flu debate in the House of Commons.

They say it's needed because a shortage of H1N1 vaccine, long lineups at overcrowded clinics, and widespread confusion are plaguing Canada's largest-ever mass-vaccination effort as it enters its second week.

Liberal MP Carolyn Bennett, the party's health critic, wrote the Speaker of the Commons on Monday asking for the debate.

"Information made public by the government in the last few days indicates that the supply and delivery of the vaccine available to local health authorities this week will fall well short of the previously announced levels," she wrote.

"Further, reports from across the country show that Canadians in high-risk groups are being turned away from vaccination centres because of lack of supply.

"The fact that many pandemic experts expect H1N1 to peak in the coming weeks adds to the urgency of the situation."

Speaker Peter Milliken was expected to rule Monday afternoon on the Liberals' request.

Thousands of Canadians have been vaccinated since Health Minister Leona Aglukkaq approved the H1N1 vaccine in late October - after other countries had already begun vaccinations.

But there have been long lineups, confusion and frustration across the country as people rush to get the vaccine and some are turned away.

Lower-than-expected production of the vaccine this week by Quebec-based manufacturer GlaxoSmithKline has meant some clinics have had to turn people away because of dwindling supply.

The drugmaker expects to ship roughly 436,00 doses of vaccine with an adjuvant - or booster compound - as well as about 225,000 doses of vaccine without the adjuvant, which are meant for pregnant women and young children.

Now public-health officials are appealing to lower-risk Canadians to wait a little longer for the swine-flu vaccine, at least until those who are most vulnerable get their shots.

But the flood of people to get the vaccine has forced at least one province to temporarily suspend all swine-flu vaccination clinics.

Alberta is facing a supply shortage after deciding last week to vaccinate everyone who wanted a flu shot, regardless of whether they were at high or lower risk.

Other provinces asked that only those deemed to be at high risk get the shot last week.

Ontario's premier said he's confident this week's rollout of the H1N1 vaccine will be better than last week's.

Dalton McGuinty admits the rollout in cities like Toronto - where pregnant women and toddlers lined up in the rain for hours last week - wasn't handled as well as it could have been.

But he says the province has now doubled the number of flu clinics, to 100 from 50 last week, to meet swelling demand.

Health officials admit they were caught off-guard by the swelling crowds at vaccination clinics. Polls leading up to the vaccine rollout suggested few Canadians planned to get the swine-flu shot.

But that was before the recent deaths of three Ontario children who caught H1N1 - with another death still unconfirmed - put a human face on the virus and galvanized worried Canadians to get themselves and their families vaccinated.