TORONTO - Ontario's governing Liberals will promise to tackle the growing problem of long waiting lists for patients in hospital emergency rooms as part of their re-election platform this fall, The Canadian Press has learned.

Liberal sources say the platform, which will be released closer to the official start of the election campaign Sept. 10, will include a plan to measure and eventually reduce wait times at hospital emergency departments.

The sources say the strategy would build on the government's existing wait-times strategy, which so far has targeted five key areas: diagnostic scans, cancer, cardiac operations, cataract surgeries, and hip and knee replacements.

"We've made progress in reducing wait times for cancer and cardiac care, and will now turn our attention to reducing the time families spend waiting in emergency rooms,'' said a senior Liberal strategist.

The Liberals point out the Progressive Conservative election platform, which was released in June, does not include any plans to address wait times in hospital emergency rooms.

But the Opposition says they've been asking the Liberals for the past two years to address problems with overcrowding and understaffing in Ontario emergency rooms, which in some cases were forced to close on weekends.

The Conservatives say the Liberals have no credibility on the issue after Advertising Standards Canada found the government's wait-times advertising was "misleading and inaccurate,'' and after the provincial auditor general said the wait-times statistics should be taken with a "grain of salt.''

"Who can believe their promises, and who can believe what they say about wait times?'' asked Conservative health critic Elizabeth Witmer.

"They were caught by the auditor and (by) the advertising council. You simply can't trust or believe the Liberal government, and you won't be able to believe them on these wait times either.''

Doctors at the Canadian Medical Association meeting in Vancouver last week overwhelmingly supported a motion calling on the provinces to develop plans to reduce emergency-room wait times and overcrowding.

The Canadian Institute for Health Information, which surveyed Ontario emergency departments in 2005-06, found 90 per cent of patients who went to major teaching hospitals were seen within nine hours, while the vast majority of patients who sought care at busy community hospitals concluded their visits within 7.5 hours.

Last January, when the survey results were released, Health Minister George Smitherman dismissed the idea of trying to reduce wait times in emergency rooms.

"We're already having a difficult time,'' Smitherman said at the time.

"Applying a standard that may in fact be artificial is not something that we have an interest in.''

NDP Leader Howard Hampton said word the Liberals will now target emergency-room wait times is yet another "flip-flop'' by Premier Dalton McGuinty.

"This is a premier who's prepared to make any promise to buy votes,'' Hampton said in an interview.

"The fact is they've had four years to address this issue and they've done nothing.''

Last fall, the Liberals committed more than $142 million for a three-point "action plan'' to help keep emergency rooms in smaller hospitals staffed with doctors on weekends and holidays, and to help reduce wait times for patients.

Dr. Alan Hudson, head of the province's wait-times strategy, will be the lead medical expert to help determine how to measure ER wait times and to devise a strategy to reduce them.