FREDERICTON, New Brunswick — A cross-border dispute between the United States and Canada about the processing of lobsters has intensified, with Canadian lobstermen insisting on higher prices for their catch while continuing to prevent Maine lobsters from reaching processors.

In the U.S., the matter reached the desk of Secretary of State Hillary Clinton on Wednesday after Maine’s U.S. Sen. Olympia Snowe urged her to investigate the growing protests in New Brunswick and other eastern provinces.

“This is an unacceptable situation that must be rectified immediately,” said Snowe, who added that the dispute could be devastating to Maine lobstermen, who are dealing with low prices for their catch on both sides of the border.

U.S. Sen. Susan Collins and U.S. Reps. Chellie Pingree and Mike Michaud also have been pressuring Canadian officials to resolve the matter.

In the New Brunswick capital, Fredericton, protestors tossed lobster traps Wednesday into the office of federal fisheries minister Keith Ashfield in an effort to get him to intervene.

The protestors succeeded in getting a sit-down meeting Friday with Ashfield, but it’s not clear whether a deal will be reached. Protestors were gone by late afternoon, and the provincial offices in Fredericton were quiet.

Premier David Alward, who spoke again Wednesday with Maine Gov. Paul LePage, said he’s been working hard to facilitate a discussion between all parties and said an open dialogue is essential to a solution.

“There has been unacceptable actions by a few fishermen, but we have had a long and fruitful relationship with Maine on trade and commerce,” Alward said in an interview late Wednesday from Fredericton.

The issue has plagued Maine lobsterman for weeks. There are too many soft shell lobsters in the water. That has forced the catch price to drop considerably. Last month, Maine lobsterman even stayed off the water several days to let the market rebound.

It didn’t. Now the problem lies across the border in Canada, where about half of all Maine lobsters are processed. Most end up being exported back to the U.S.

Canada’s lobstermen don’t want their processors buying Maine lobsters at such a low price and are hoping the provincial government will step in; but processors are paying what the market will bear, about $2.50 to $3 per pound. Canadian lobstermen want $4.

Alward said New Brunswick would not subsidize lobster prices. They have offered some compensation to lobstermen in the form of deferred loan payments, but the lobstermen’s union rejected the offer.

In recent days, Canadian lobstermen have blocked the entrance of some processors in New Brunswick, Nova Scotia and Prince Edward Island. Some, including Snowe, fear those confrontations could escalate into violence,

Officials at the U.S. Embassy in Canada told Snowe’s office that the senator’s concern about “acts of intimidation, violence, or coercion” were forwarded to the Royal Canadian Mounted Police in New Brunswick.

Alward said he is concerned about safety, too, but was confident that cooler heads would prevail.

Patrick Keliher, Maine’s Department of Marine Resources commissioner, said a handful of processors, particularly on Prince Edward Island, are agreeing to process only the Maine lobster they have on hand.

Canadian lobstermen also have delayed their season to put further pressure on processors and the government. The problem across the border seems to be more complicated and involves in-fighting within the Maritime Fisheries Union, according to Canadian press accounts.

Mainers who rely on lobsters for their livelihood can do little but watch.

Pete Daley, vice president of Garbo Lobster in Hancock, had one of his trucks stopped in New Brunswick last week. He hasn’t sent any more since.

“We’re in daily communication with the processors; but until they tell me I can ship our product, we’re not going to risk it,” he said Wednesday from his company’s headquarters. “It’s a volatile situation, and I don’t want to say anything to inflame it.”

Sara Griffin of Quoddy Bay Lobster in Eastport said the fishermen she’s heard from this week are frustrated.

“I think they would like to see more processing done here in Maine, but that hasn’t happened,” she said from her business, a combination retail shop/wholesale distributor that overlooks the water in one of Maine’s easternmost communities.

With Canadian processors refusing to take Maine lobster, Commissioner Keliher said he’s worried about a backlog of lobster in Maine, basically a repeat of the July glut that caused prices to crater. Maine lobstermen had pinned hopes for a recovery on the Canadian plants, where shipments resumed once Maine fishermen started to catch lobsters whose shells were hard enough to survive shipment.

Keliher said prices paid to lobstermen in Maine on Tuesday were about $2.25 to $2.75 a pound, near the record lows hit last month.

Maine lobstermen expressed sympathy for the Canadians’ plight but decried their tactics.

“The Maine Lobstermen’s Association is in complete sympathy with the economic situation facing Canadian fishermen but strongly rejects methods that disrupt, threaten, interfere with or otherwise impose obstacles on international commerce,” Patrice McCarron, the executive director of the association, said in a statement.