White House’s acting chief of staff Mick Mulvaney has gone “noticeably quiet” during President Trump’s impeachment inquiry, reports Politico.

Mulvaney, the grandson of Co Mayo immigrants who replaced Irish American John Kelly as the president’s top aide last year, “has found his influence dwindling inside the West Wing” and is reportedly being sidelined by Trump.

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“Mick is lying low, but everyone is lying low,” said a former senior administration official. “White House aides are hoping the president deals with this himself, and everyone is trying to keep their heads down.”

“Popping your head up will only lead to bad things,” this person said. “It’s uncommon for a chief to do this as well, but Mick seems to be in the same shelter-in-place posture everyone is in.”

Chris Whipple, author of The Gatekeepers: How the White House Chiefs of Staff Define Every Presidency, said: “The central question here is: Where is Mick Mulvaney? He's abdicated the most important duty as White House chief of staff, and that is telling the president what he doesn't want to hear. And the most dramatic result of his ‘Let Trump be Trump’ posture is the Ukraine scandal. He should have thrown his body in front of that phone call.”

He added: “It’s hard to discern any impeachment strategy whatsoever, so it makes it really hard to judge what Mulvaney is or isn’t doing.”

Several sources say that Mulvaney’s job is safe, partly because Trump would not be able to find a substitute amid impeachment proceedings and partly because Mulvaney is too enmeshed in the Ukraine scandal.

However, Trump’s unpredictably has created an atmosphere of uncertainty for everyone around him. including Mulvaney.

“This is the point in Trumpworld where they figure out who to blame,” a second former administration official told Politico.

Allies of Mulvaney said he is content to maintain a low profile for now, but he would be ready to make a graceful exit if necessary.

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“Mick, in general, is someone who likes to keep his options open,” said a former White House official.

"I don't think he's ever viewed this role as something he would do forever,” said another Mulvaney ally. “If his plan was to stay for a very long time, he would have pushed for a title change. If he got a real sense that the president wants somebody else, he's not going to fight that. He is in good standing with Trump right now, but this is a hard time for anybody. So, it wouldn't shock me if he‘s thinking about what he wants to do next."

White House Chief of Staff Mick Mulvaney.