Nor will it hinder further progress, said Wall, who chairs the group with Prince Edward Island Premier Robert Ghiz.
"As of late, Quebec has been more of a distraction at this table than a constructive partner," Wall said Tuesday in an email released to The Canadian Press by his office.
"We have been making significant progress in areas like joint purchase of generic drugs, sharing best practices, bending health-care cost curves and improving patient care without a lot of input from Quebec."
The premier was not available for further comment.
Quebec's decision to pull out of the group was made public Monday. It had been quietly announced in a letter dated Jan. 11 and signed by Health Minister Rejean Hebert and Intergovernmental Affairs Minister Alexandre Cloutier. Quebec said it intended to concentrate on its own priorities.
"What we're saying is simply that we don't want to add to existing structures. We want an efficient government. Health care is a responsibility of the Quebec government," Cloutier said in an interview Tuesday with The Canadian Press.
"We're ready to co-operate, to share information. We certainly don't want to duplicate activities that already exist, with an increased role for the federal government.
"It's a working group that established priorities not shared by the government of Quebec."
The health-care group was created in January 2012 by the Council of the Federation. The federation was created in 2003 by premiers — including former Quebec premier Jean Charest, a staunch federalist — to promote interprovincial and territorial co-operation.
The health group's goal is to look at better ways to deliver health care and keep it sustainable.
Last month, Wall announced the provinces would bulk buy six widely used generic drugs. He suggested the initiative could save provincial and territorial drug plans up to $100 million once it is fully implemented. Quebec was the only province to say it would not take part.
Federal NDP Leader Tom Mulcair said working together has produced good results for Canadians.
Although provinces are responsible for health-care delivery, "we've agreed over the years on everything from an information highway ... to the possibility ... if we start adding more and more drug coverage, we could start moving towards better shared purchases," said Mulcair.
"That could be one of the possibilities to reduce costs on a very strapped system right now, so one would always hope to see everyone work together on these issues."
— With files from Alexandre Robillard in Quebec City and Joan Bryden in Ottawa
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