A Republican megadonor with ties to Long Island reportedly played a key role in persuading Steve Bannon to not resign as one of President Donald Trump’s top White House advisers.

Rebekah Mercer, the daughter of Long Island billionaire Robert Mercer, urged Bannon to remain in his post as White House chief strategist, despite his growing frustration over infighting in the fledgling administration, according to a report published late Wednesday night by Politico that cites five sources close to Trump and the White House.

The report came as multiple White House sources told the New York Times and Politico on Wednesday that Bannon threatened to quit over his removal from the National Security Council’s principals committee, a top-level panel tasked with shaping national security policy.

On Thursday, Bannon, the former head of right-wing news outlet Breitbart News who led the final leg of Trump’s presidential campaign, denied the reports, telling ABC News the claims were “absurd.” Bannon in a statement to reporters, said his appointment to the NSC was only meant to be temporary.

Meanwhile, a source close to the White House told Politico that Mercer, who recruited Bannon to join Trump’s campaign last summer “prevailed upon him to stay” and a GOP operative who speaks frequently to Mercer, 43, told the outlet that “Bekah tried to convince him that this is a long-term play.”

Rebekah Mercer, and her father Robert, 70, the CEO of Renaissance Technologies, an East Setauket-based hedge-fund, have been credited with reshaping Trump’s presidential campaign last summer. The family, which owns a stake in Breitbart News, recruited Bannon to lead Trump’s campaign team.

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A call to the Mercer Family Foundation seeking comment on the Politico story was not immediately returned Thursday.

Bannon’s future in shaping Trump’s agenda has come into question among White House observers now that the president has expanded the responsibilities of his son-in-law Jared Kushner, who serves as a top adviser, and has added his daughter Ivanka Trump to his team of White House advisers.

Bannon’s removal from the NSC, just months after his controversial appointment to the panel “indicates that the White House is still in a state of transition,” said Meena Bose, director of the Hofstra University’s Peter S. Kalikow Center for the Study of the American Presidency.

“The future influence of Steve Bannon is an open question at this point,” Bose said. “His removal from the NSC principals committee . . . the increasing formal White House roles for the president’s daughter and son-in-law, these things combined suggest that there is some shifting of power in the president’s inner circle.”