President Trump vowed Friday to open the nation’s only national monument in the Atlantic Ocean to commercial fishing, saying he was giving Maine back part of its history and the fishermen their industry.

He signed a proclamation declaring the opening after attending a roundtable discussion with commercial fishermen in Bangor, Maine, that included a wide-ranging conversation about unwanted regulations and tariffs on the seafood trade.

“We’re opening it today,” Trump said. To the fishermen, he added: “We’re gonna solve your fishing problem....Basically, they took away your livelihood. It’s ridiculous.”

Trump’s move to open fishing in the Northeastern Canyons and Seamounts Marine National Monument will surely open a new front in the ongoing legal battle over the limits of presidential powers regarding national monuments.