AUGUSTA — Maine officials have reluctantly canceled the monthlong fishing season for Atlantic salmon scheduled to begin this Friday in the latest possible sign of escalating tension between the state and the federal government over the imperiled fish.

The sudden reversal came after federal regulators met with Gov. John Baldacci and the Atlantic Salmon Commission last week to discuss the pending decision about whether Maine salmon will be added to the endangered species list.

During that meeting, representatives from the National Marine Fisheries Service apparently reiterated their strong opposition to a catch-and-release season for Atlantic salmon on the Penobscot River.

“[The governor] had a conversation with the commission and after that conversation the commission decided it should reconsider the fishery,” Patrick Keliher, director of the Department of Marine Resources’ Bureau of Sea-Run Fisheries and Habitat, said Wednesday.

Baldacci was occupied with Maine’s response to the emerging swine flu epidemic on Wednesday and was not available for comment, the governor’s staff said.

Dick Ruhlin, chairman of the three-member salmon commission, said in a phone interview that as an angler he was “extremely disappointed” that the season has been scrapped. But Ruhlin said he had a responsibility to the recovery of Atlantic salmon, which have been virtually wiped out from their former range in the United States.

“It became clear to us that we would be endangering the Atlantic salmon restoration project from a public relations aspect if we had anything go wrong during the recreational fishery,” Ruhlin said Wednesday evening.

But Ruhlin’s additional statement that “the era of cooperation is over” between the state and federal regulators highlights the frustration underlying the canceled season.

Federal officials are expected to announce in the coming weeks whether salmon in three of Maine’s largest rivers — the Penobscot, the Kennebec and the Androscoggin — will be protected under the Endangered Species Act.

The Penobscot River is the only U.S. waterway that still sees a sizeable run of spawning Atlantic salmon. But more than 90 percent of the returning fish can be traced to two federal fish hatcheries, and the 1,000 or so fish that typically return to the river annually are a fraction of historic runs.

Baldacci, DMR officials and the salmon commission have urged the federal agencies to list the fish as “threatened” rather than “endangered.” Maine officials have said a threatened listing would still protect the fish but could give the state more flexibility, especially when dealing with some of the large industries located along the rivers.

While federal regulators have not told the state of their decision, they are widely believed to have settled on the more restrictive designation of endangered.

The last-minute decision to cancel the fishery will undoubtedly anger some die-hard anglers and advocates for a catch-and-release season, however. Ruhlin said any anglers who bought the special salmon-fishing permit would receive refunds.

“It’s just tragic that they did that to us,” said Lou Horvath, a former president of the three salmon clubs located along the Penobscot. Horvath said the decision is already harming efforts to raise money from fishermen to remove three dams along the Penobscot in order to open up nearly 1,000 miles of the watershed to salmon and other sea-run fish.

Friday would have been only the second “opening day” for spring salmon fishing on the Penobscot in a decade. The state held an identical catch-and-release season last spring, again over the vocal objections of federal officials.

While fewer than 200 fishermen participated last spring — resulting in a financial loss for the state — the commission and DMR staff said the season proved that the state could run a carefully monitored fishery without harming the population. Anglers were restricted to using single-pointed, barbless flies and were required to re-lease all fish immediately.

In fact, just two weeks ago, Ruhlin said risk assessments conducted before the season and subsequent analyses clearly showed there was no harm done to the salmon restoration efforts.

Ruhlin made his comments during a commission meeting in which the three-member board directed staff to continue preparing for the season. But at the same meeting, a National Marine Fisheries Service representative made clear her agency’s continued opposition.

“We believe having a directed fishery this year is not a biologically reasonable thing to do, and we recommend you reconsider,” said Mary Colligan with the service’s protected resources division in Massachusetts.

Colligan could not be reached for comment Wednesday.