• Former Treasury Secretary Steven Mnuchin has been keeping his distance from Donald Trump after years of serving in the White House.
• Mnuchin, who was one of Trump's most loyal advisors and an architect of the administration's tax cut plan, has not been involved with calls or meetings featuring Trump and the former president's economic advisors.
• Mnuchin decision to not help Trump, at least for now, comes after he was reportedly furious with the then president following the deadly riot on Capitol Hill on Jan. 6, 2021.

After serving in the Trump administration for four years, former Treasury Secretary Steven Mnuchin is keeping his distance from the Republican former president and his campaign, according to people familiar with the matter.

"Mnuchin has not been in the room," said Stephen Moore, a conservative economist who is advising Trump. "I don't know if it's Mnuchin being done, or maybe there was a falling out between the two."

Mnuchin was one of Trump's most loyal Cabinet secretaries and an architect of the administration's tax cut plan. But so far in the 2024 race, Mnuchin has not been involved in calls or meetings between Trump and the former president's economic advisors.

Those advising Trump on economic policies include Larry Kudlow, an anchor at Fox Business and a former director of the National Economic Council, and Bob Lighthizer, former United States trade representative during Trump's first term in office, NBC News reported.

Mnuchin's absence means Trump is without a trusted advisor and a steady hand who played a key role in his first campaign for president, and later implemented some of Trump's most popular policies.

Now, Trump's campaign is eager to highlight these policies to remind voters of the "Trump economy," an era of tax cuts and low inflation, and to draw a sharp contrast with President Joe Biden's first term.

A person close to Mnuchin who was granted anonymity in order to recount private conversations, said Mnuchin supports Trump's 2024 run for president. But they did not know whether that support would translate into actively helping Trump in the primary or the general election.

Over the years, Trump has benefited from more than just Mnuchin's counsel.

In 2016, Mnuchin was Trump's national finance chairman during his first run for the White House. In that role, the well-connected Mnuchin tapped his networks to help the long-shot candidate raise millions of dollars to take on establishment Democrat Hillary Clinton.

For now, Mnuchin's private equity firm, Liberty Strategic Capital, takes up most of his time, people close to the former secretary told CNBC. The firm raises money from sovereign wealth funds in the Middle East.

Press representatives for Trump and Mnuchin did not return a request for comment.

Mnuchin was reportedly furious with Trump after the Jan. 6, 2021, attack on the Capitol, and he privately fumed over how long it took Trump to finally address his supporters as they ransacked the Capitol, according to The Washington Post.

Mnuchin later told a House select committee that he and Secretary of State Mike Pompeo spoke that day about invoking the 25th Amendment, to force Trump from office and allow Vice President Mike Pence to take his place.

"It [the 25th Amendment] came up very briefly in our conversation. We both believed that the best outcome was a normal transition of power, which was working, and neither one of us contemplated in any serious format the 25th Amendment," Mnuchin told the committee.

Just as other Republicans did in the weeks after the attack, Mnuchin publicly condemned the violence but did not personally criticize Trump.

Mnuchin's situation mirrors that of many Trump Cabinet officials who have quietly kept their distance from the former president, since he left office in 2021.

Former National Economic Council Director Gary Cohn and former Commerce Secretary Wilbur Ross have each been involved with the 2024 election but have notably not taken on Trump. NBC News contacted 44 Trump White House officials last year. Of the 44, only four said he should be reelected.

Cohn has helped raise money for the presidential campaigns of former U.S. Ambassador to the United Nations Nikki Haley and Sen. Tim Scott, R-S.C., two of Trump's Republican primary rivals. Haley has been surging into a distant second place behind Trump with the Iowa caucus scheduled for Jan. 15, according to a Real Clear Politics polling average.

Scott dropped out of the race for president late last year.

Ross has also stayed involved with politics since the start of the 2024 election but has remained noncritical of Trump. Ross hosted a fundraiser for Virginia Gov. Glenn Youngkin, who at the time was not ruling out running for president in the Republican primary.

Youngkin told CNBC in a recent interview that he would support Trump if he became the 2024 Republican nominee for president.

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