The Alberta government is imposing a contract on the province's doctors after the two sides hit an impasse after 20 months of negotiations.

The plan, announced Friday by Health Minister Fred Horne, is based on the offer the province presented to the Alberta Medical Association in October.

The news came as a shock to AMA president Dr. Michael Giuffre.

"I would have to say I was very surprised. I would in fact say I was somewhat shocked. I think it's the first time in the history of Alberta that such an imposition has occurred," he said.

Horne told reporters that the government decided to impose the contract after negotiations with the AMA had reached an impasse.

"I had laid out very clearly what was the best the government could do and those increases are provided for in the plan," Horne said.

"The Alberta Medical Association was looking for something considerably more than that and it was clear to me that we weren't going to be able to bridge that gap."

Giuffre said that talks reached an impasse Thursday night and he believes Horne acted on his own to impose a deal.

"I can tell you that the initial preconditions that the minister put on the table for us to consider is the exact final offer that was on the table, there was no consideration of our counter-offer," he said.

"There was no true process of negotiation. This was truly an imposition in the sense of the word 'imposition.'"

Physician and Alberta Liberal Leader Raj Sherman said the government's action will have consequences.

"The relations in Alberta between the physicians and this government are the worst in the country," he said, adding that morale has been low for years.

"This is only going to make those relationships even worse."

The contract includes a one-time lump sum payment of 2.5 per cent to each doctor based on their billings in 2011-12 and annual increases tied to the Cost of Living Adjustment in 2013-14, 2014-15 and 2015-16.

The province will continue the $12 per-patient increase for Primary Care Networks to the end of 2015-16 and keep the Business Cost Program to the end of 2014.

The changes are valued at $463 million over four years.

Horne said that Alberta doctors are paid 29 per cent above the national average.