"We have a minister who has essentially ignored us for two years, entered into numerous processes of negotiation and then backed out, and is now hitting us with a (budget) cut at the end of it," said Dr. Michael Giuffre, the head of the Alberta Medical Association.
"We will not participate in a process to cut $275 million from the physician services budget."
Horne has said the money is needed to pay for the services of 300 new doctors entering the system this year. He had asked doctors to submit suggestions by Friday on the best way to make that happen with the least impact on patient care.
Giuffre said Horne has not made his case that the cut is even needed.
"It behooves the minister to now tell us if he's going to make cuts, where do these cuts come from? Where do they go? What procedures, what surgeries, what access does he want to cut for the patients of Alberta?"
Giuffre also wrote a public letter to Premier Alison Redford, urging that she reprimand Horne for breaking promises to doctors during negotiations over the last year.
He also said Horne has hidden key financial numbers and imposed short, arbitrary deadlines that have hindered the process.
"The AMA respectfully requests that you instruct Minister Horne to cease his untrustworthy behaviour toward Alberta's physicians," said the letter to Redford.
Horne said that he and Redford discussed Giuffre's latest comments and remain united.
"We're disappointed that the president has chosen to make this personal, to engage in a personal attack, particularly upon myself," said Horne.
"It's offensive and disappointing, but we're not going to get into that kind of a response.
"The goal here is still to get a negotiated agreement with the AMA, and what we need to be doing is focusing on that work."
The doctors have been without a contract for two years, but negotiations became acrimonious after Horne imposed a wage deal on the doctors four months ago and then withdrew it in the face of widespread criticism.
Since then, the province has passed an austere budget for 2013-14 that caps money for doctors' salaries at $3.4 billion and offers no room for salary hikes.
Giuffre has said with physicians' business costs rising, the $3.4-billion cap equates to slashing salaries by 20 per cent or more over the next few years. He said the cuts would affect front-line patient care.
On top of the $3.4-billion cap, Horne announced this week the province needs the extra $275 million.
Horne said he has always bargained in good faith and will continue to do so. He said the extra money must be found whether doctors help or not.
"I suppose if we can't get the AMA organization to participate, then there will come a time where we have to have a plan in order to make sure that we stay within budget. I'm hopeful that they might reconsider," he said.
"I don't think scaring patients is the answer to this. And I don't think a public relations war is the answer to this. The answer lies at the negotiating table."
Horne declined to set a deadline for a deal, but said without an agreement the province will need some kind of operating plan for the coming year to stay within the $3.4-billion limit.
Giuffre said the AMA is eyeing a legal challenge to the government on the grounds of bad-faith bargaining.
The AMA represents Alberta's 8,000 physicians.
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