WASHINGTON, United States (AFP) — Green groups on Wednesday launched the first environmental challenges against the new Trump administration, targeting the president’s plans to expand offshore drilling.

The first lawsuit challenges an executive order that revokes former president Joe Biden’s withdrawal of vulnerable ocean areas from future oil and gas leasing.

The second lawsuit seeks to reinstate a federal court ruling that previously invalidated efforts by Donald Trump’s first government to overturn offshore protections established by former president Barack Obama.

Trump has moved to open much of the Arctic Ocean to drilling by reviving his first-term order.

Late in his term, Biden protected areas off the Eastern Gulf, as well as the Atlantic, Pacific, and Alaska coasts, invoking the Outer Continental Shelf Lands Act.

But environmental groups argue that the law does not grant the president authority to revoke withdrawals made by previous presidents. They cite a federal court ruling from Trump’s first term when he attempted to undo Obama-era protections.

“We defeated Trump the first time he tried to roll back protections and sacrifice more of our waters to the oil industry. We’re bringing this abuse of the law to the courts again,” said Earthjustice managing attorney for oceans Steve Mashuda.

“Trump is illegally trying to take away protections vital to coastal communities that rely on clean, healthy oceans for safe living conditions, thriving economies, and stable ecosystems.”

Oceana campaign director Joseph Gordon added: “President Trump’s executive order would roll back millions of acres of ocean protection, jeopardising our coastal economies and the people who rely on healthy, thriving oceans.”

On his first day back in office, Trump announced the United States’ withdrawal from the Paris Climate Accord for a second time, declared a “national energy emergency” to expand drilling, and signed executive orders to slow the transition to electric vehicles and halt offshore wind farm projects.