California's chief prosecutor and an environmental commission on Monday filed a lawsuit challenging an assessment by federal authorities that clears the way for hydraulic fracturing off the state's coast.

The lawsuit from Attorney General Kamala Harris and the California Coastal Commission targets the US Department of the Interior as well as two federal agencies.

The federal agencies in May said that an environmental assessment had determined that fracking poses no significant impact, clearing the way for a moratorium on the controversial form of gas and oil extraction to be lifted.

"We must take every possible step to protect our precious coastline and ocean," Harris, who was elected to the US Senate in November and will take up her new post next month, said in a statement.

"The US Department of Interior's inadequate environmental assessment would open the door to practices like fracking that may pose a threat to the health and wellbeing of California communities."

The legal challenge comes just days after California's governor Jerry Brown urged President Barack Obama to permanently ban all new offshore oil and gas drilling in federal waters off California's coast before he leaves office in January.

Environmental groups and California's two senators have also called on Obama to protect California's coastline by taking advantage of a federal law.

Brown's appeal and the lawsuit filed on Monday have taken on more urgency given President-elect Donald Trump's nomination of several Republicans with ties to the oil and gas industry to key posts in his administration.

Among them is ExxonMobil CEO Rex Tillerson, who was nominated to be secretary of state, and Scott Pruitt, the attorney general of the oil and gas-producing state of Oklahoma, to head the Environmental Protection Agency.

Hydraulic fracturing involves pumping large quantities of water and chemicals at high pressure deep into the Earth to fracture rock to stimulate the flow of natural gas or oil.