The House Democrat expected to lead the committee that will oversee the Interior Department is calling for its secretary, Ryan Zinke, to resign. And Zinke has fired back with charges of heavy drinking and his own call for Arizona Rep. Raúl M. Grijalva to step down.

Grijalva is in line to take over the House Natural Resources Committee in January and he penned a scathing USA Today op-ed, published Friday, that went straight to the point with this opening sentence: “Ryan Zinke needs to resign immediately as Secretary of the Interior.”

“Mr. Zinke has never even tried to offer an explanation for the sheer scope of his well-documented scandals,” Grijalva wrote of a Montana real estate scandal involving the former GOP congressman and allegations of travel-related ethical violations since he took over the Interior Department.

“This silence is insulting to the American people, and given the Nov. 6 election results it is unsustainable. Continuing in office as though nothing has changed only shows how little Mr. Zinke has learned over the past year and a half,” the Democrat wrote.

“He holds his job as a public trust, not as a stepping stone to his further personal ambitions. He has abused that trust and damaged the Interior Department in the process. The least he can do is step down and give his successor a chance to begin reversing that damage,” Grijalva added.

He also accused Zinke of overseeing “the degradation of his department’s senior work force in the name of enforcing ‘loyalty’ to himself and the Trump administration; announced his intention to cut thousands of permanent positions; prompted mass resignations from a nonpartisan National Park Service advisory board by refusing to meet with members; and tied his own employees and aides in knots to make himself and his wife more financially comfortable.”

Signaling a bitter fight ahead if Zinke stays in his role — President Donald Trump has said he is looking into all the allegations against the secretary — and Grijalva does indeed take the Natural Resources gavel, Zinke fired back with a personal attack Friday. And it had all the hallmarks of the kind of sharp rhetoric used by his boss.

The secretary issued his response on Twitter, writing this: “My thoughts on Rep. Grijalva’s opinion piece. #TuneInnForMore,” using that hashtag to refer to a popular Capitol Hill bar that Grijalva has been known to frequent. His actual statement was less subtle about the congressman and alcohol consumption.

“It’s hard for him to think straight from the bottom of the bottle,” Zinke said. “This is coming from a man who used nearly $50,000 in tax dollars as hush money to cover up his drunken and hostile behavior.”

The secretary appeared to be referring to a November 2017 Washington Times report that Grijalva arranged a “severance package” for a female aide that included $48,000 in extra pay in return for her silence after she alleged he was often intoxicated and created a hostile work environment.

“He should resign,” Zinke wrote of Grijalva, “and pay back the taxpayer for the hush money and the tens of thousands of dollars he forced my to spend investigating unfounded allegations.”

Jennifer Rokala, executive director of the nonpartisan Center for Western Priorities, said in a statement that the secretary’s response is “even by Secretary Zinke’s standards … a new low.”

“It’s unbecoming of a Cabinet secretary. It’s also foolish to pick a fight with a member of Congress who will soon have oversight and subpoena power over your agency,” she said. “We, and the American people, look forward to full investigations into Secretary Zinke’s unprecedented and ongoing ethical lapses.”

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