In protecting the waters, Obama used a 1950s-era law called the Outer Continental Shelf Act that allows presidents to limit areas from mineral leasing and drilling. Environmental groups said Obama's use of the law meant the incoming administration of Republican President-elect Donald Trump could not simply reverse the action but would have to fight it in the courts.
The ban affects federal waters off Alaska in the Chukchi Sea and most of the Beaufort Sea and in the Atlantic from New England to Chesapeake Bay.
