Interior Secretary Ryan Zinke is stepping down, President Donald Trump announced Saturday.

Trump said Zinke would be leaving at the end of the year and his replacement would be announced next week.

Zinke is at the center of sharp scrutiny for a number of incidents that have sparked ethics probes, including using thousands of dollars of taxpayer money for a helicopter ride.

Interior Secretary Ryan Zinke is stepping down, President Donald Trump tweeted Saturday morning.

Trump wrote that Zinke would be leaving the administration at the end of the year after a two-year stint in the White House and that he would be naming a replacement next week.

The embattled secretary's departure comes amid the pressure of numerous ethics probes into a series of questionable expenditures, including reportedly spending thousands of dollars in taxpayer funds for a government helicopter ride to arrive on time for a horseback ride with Vice President Mike Pence. Another revolved around a lucrative real-estate deal in his Montana hometown that involved oil giant Halliburton, a company the Interior Department regulates.

Zinke has previously had similar issues related to his use of government funds. While on official military orders in the late 1990s, he made some restoration work on a childhood home and was eventually forced to repay some unauthorized expenses to the Navy, Outside magazine previously reported.

In his resignation letter obtained by the Associated Press, Zinke said "vicious and politically motivated attacks" against him had "created an unfortunate distraction" in his time at the head of the agency.

In the letter, the former Montana congressman also lambasts "meritless and false claims" and says "to some, truth no longer matters."

Democratic lawmakers spoke out about Zinke's departure, referencing his hefty record of sparking ethics concerns as evidence he was a problematic administration member.

"Ryan Zinke was one of the most toxic members of the cabinet in the way he treated our environment, our precious public lands, and the way he treated the govt like it was his personal honey pot," Senate Minority Leader Chuck Schumer tweeted Saturday. "The swamp cabinet will be a little less foul without him."

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Zinke was previously reported to be considering a departure for a job opportunity with Fox News as a contributor.

Both Fox News and the Interior Department denied that talks had taken place. One Interior Department official told Business Insider that the report was "completely fabricated," while a Fox News spokesperson said that "no one at Fox News has spoken to Zinke about a contributor role."

Zinke is the second major administration personnel departure in a week, following White House Chief of Staff John Kelly's departure and the reported struggle to replace him before Mick Mulvaney, the director of the Office of Management and Budget, was tapped.