US president-elect Joe Biden will nominate Deb Haaland to serve as his interior secretary, making her the first Native American in the US Cabinet.
Ms Haaland has been the leading candidate for the job of overseeing the department, a source said.
It employs more than 70,000 people across the US and oversees more than 20 per cent of the nation's surface, including tribal lands and national parks such as Yellowstone and Yosemite.
Ms Haaland, a Democratic congresswoman from New Mexico since 2019 and a member of the Laguna Pueblo tribe, recently said she would try to introduce an expansion of renewable energy production on federal land.
This would contribute to the fight against climate change and undo President Donald Trump's work on increasing fossil fuel output.
“Leasing practices need to be changed," Ms Haaland said. "We need to make sure we’re promoting and increasing clean-energy leases."
She said she supported conserving 30 per cent of federal land by 2030 and using the Antiquities Act to protect culturally and ecologically sensitive land such as national monuments.
Those positions clash with Trump administration efforts to maximise coal mining and drilling on public lands, and to shrink the size of national monuments created by past presidents.
Ms Haaland's nomination came after weeks of heavy campaigning by Native American groups and leaders, progressive activists, and some Democratic and Republican legislators.
Fawn Sharp, president of the National Congress of American Indians and of the Quinault Indian Nation in Washington state, said Ms Haaland's appointment signals the Biden administration will focus on some indigenous country priorities.
"It's important to have a high-level Native American perspective at the table," Ms Sharp said.
"Haaland would be effective especially around climate change, protecting sacred sites on tribal lands and restoring lands that have been administratively taken from tribes."
If nominated, Ms Haaland would step down from her seat in the US House, where Democrats are already facing a slim majority in 2021 after losing seats in the 2020 election.