Environmental groups applauded President Joe Biden’s decision on Monday to enact a sweeping ban on new offshore oil and gas drilling along most of the U.S. coastline. But the ban had one glaring omission: It didn’t include the western Gulf of Mexico, where the country extracts most of its offshore oil.

President Joe Biden on Monday announced an executive action that will permanently ban future offshore oil and gas development in parts of the Atlantic and Pacific oceans in a way that could be especially difficult for the incoming Trump administration to undo.

Landmark decision affects 625 million acres on Pacific Coast, Atlantic Coast, western Gulf of Mexico and parts of Alaska