EBy ELLEN KNICKMEYER and JONATHAN LEMIRE
WASHINGTON (AP) — Interior Secretary Ryan Zinke, who is facing federal investigations into his travel, political activity and potential conflicts of interest, will leave the administration at year's end, President Donald Trump said Saturday — an announcement that was immediately welcomed by environmentalists.

Trump, in tweeting about Zinke’s departure, said the former Montana congressman “accomplished much during his tenure” and that a replacement would be announced next week. The Cabinet post requires Senate confirmation.
Zinke is leaving weeks before Democrats take control of the House, a shift in power that promised to intensify probes into his conduct. His departure comes amid a staff shakeup as Trump heads into his third year in office. The president on Friday named White House budget director Mick Mulvaney as his next chief of staff
Zinke, 57, played a leading part in Trump's efforts to roll back environmental regulations and promote domestic energy development. When he recently traveled to survey damage from California’s wildfires, Zinke echoed Trump claims that lax forest management was to blame in the devastation.
He pushed to develop oil, natural gas and coal beneath public lands in line with the administration's business-friendly aims. But Zinke has been dogged by ethics probes, including one centered on a Montana land deal involving a foundation he created and the chairman of an energy services company that does business with the Interior Department.
Investigators also are reviewing Zinke’s decision to block two tribes from opening a casino in Connecticut and his redrawing of boundaries to shrink Bear Ears National Monument in Utah.
Zinke has denied wrongdoing.
The Associated Press reported in November that the department's internal watchdog had referred an investigation of Zinke to the Justice Department.
Trump told reporters this fall he was evaluating Zinke's future in the administration in light of the allegations.
Asked by reporters in November whether he might fire Zinke, Trump said, ”No, I'm going to look into any complaints.”
Zinke in November denied that he already was hunting for his next job.
“I enjoy working for the president,” he told a Montana radio station. “Now, if you do your job, he supports you.
“I think I'm probably going to be the commander of space command,” Zinke said. “How's that one?”
But environmentalists saw nothing lighthearted about Zinke’s tenure.
The executive director of the Center for Biological Diversity said: “Zinke will go down as the worst Interior secretary in history. His slash-and-burn approach was absolutely destructive for public lands and wildlife.”
But in his statement, Kieran Suckling said that Zinke’s departure does not mean the Trump administration will stop its efforts to roll back environmental regulations and promote energy production. He said it will be characterized by the “same appetite for greed and profits.”
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