Before he leaves, President Obama has designated almost 1.6 million acres of land in Nevada and Utah as national monuments to protect Native American burial grounds and sacred sites. This is seen as another swipe against the incoming Trump administration since the 1.35 million acres in Utah will effectively end new oil and gas exploration leases (via The Hill):

The actions further cement the aggressive conservation legacy of Obama, who has protected more land and water than any other president under the Antiquities Act.

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The 1.35 million-acre Bears Ears area could be the most controversial of Obama's dozens of national monuments, in part because it shuts down any new leases for mining or oil and natural gas, exploration, along with other development and potential harms.

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But Sen. Mike Lee (R-Utah) slammed Obama’s decision.

“This arrogant act by a lame duck president will not stand,” Lee tweeted Wednesday.

“I will work tirelessly with Congress & incoming Trump administration to honor the will of Utahns and undo this monument designation,” he added.