U.S. Interior Secretary Ryan Zinke will step down at the end of 2018, President Donald Trump tweeted Dec. 15, amid a series of investigations into his travel, political activity and potential conflicts of interest.
Trump said Zinke's successor will be announced in the week of Dec. 17.
The latest high-profile departure from Trump's administration comes as Democrats pledged to deepen scrutiny of his conduct after taking control of the House of Representatives. Zinke's decision was in part driven by concerns about heightened scrutiny and potential legal costs, Bloomberg News reported.
A former Navy Seal, Zinke pushed for U.S. energy dominance, promoting oil drilling and coal mining, reducing royalty rates and easing land protections. While that earned him praise from U.S. energy and mining advocates, he also became a target for environmental groups.