RENO, Nev. (AP) — Environmentalists have filed an anti-fracking lawsuit in Nevada to block an effort to expand oil and gas drilling on federal land.

Two national conservation groups say the Bureau of Land Management is reversing course from policies it enacted in the final weeks of the Obama administration that limited drilling on a vast stretch of federal land in Nevada.

The Sierra Club and Center for Biological Diversity say the government failed to consider potential consequences of hydraulic fracturing ranging from harm to sage grouse to contamination of water resources.

They say it's the first time the BLM has specifically reversed a draft proposal to keep some otherwise unprotected lands off limits to energy exploration since President Donald Trump assumed office in January.