Gov. Paul LePage has written to President Obama and the state’s congressional delegation to oppose the idea of establishing two national monuments in Maine.

LePage wrote to Obama Friday to express disapproval of a proposal to designate areas within the Gulf of Maine as a national maritime monument. Obama has the authority to establish national monuments under the Antiquities Act.

The proposal would designate Cashes Ledge and undersea canyons and seamounts in the gulf as a national maritime monument. LePage said the designation would hurt offshore lobstermen and those seeking groundfish and tuna.

“Maine’s economy is heavily dependent on natural resources-based industries and these types of designations harm working Mainers the most,” wrote LePage. “These National Maritime Monuments serve only one purpose – excluding commercial fishing activity from certain segments of the ocean.”

Obama has not provided a timeline for potential designation, and the governor requested information about the timing.

LePage also sent a letter Friday to the four members of Maine’s congressional delegation outlining his concerns about presidential authority under the Antiquities Act and access to Maine’s natural resources.

The governor said some proponents of creating a national park in the Millinocket area are considering seeking national monument designation as an alternative, following recent anti-park votes on ballot questions in Medway and East Millinocket.

“A National Monument designation makes Maine timber off limits to the forest products industry,” LePage wrote. “As you all know, so much of Maine’s economy relies on access to our natural resources. The President’s authority under the Antiquities Act puts Mainers at risk by making these natural resources off limits.”

He urged the delegation to oppose both national monument proposals and asked them to take steps to revise the Antiquities Act and reduce presidential authority under the law.