The departure was treated with some mystery. Sean Spicer, the White House press secretary, would not comment on the reason Mr. Epshteyn, an old friend of President Trump’s son Eric, was expected to depart the post.
A senior administration official, speaking on the condition of anonymity, said only that officials were exploring other opportunities in the administration for Mr. Epshteyn, who at one point was on cable news as many as seven times a day promoting Mr. Trump during the presidential campaign.
Two people familiar with Mr. Epshteyn’s tenure said he had become combative with the networks on which he was assigned to book surrogates defending the administration, a junior position for someone who has other news media experience, which he does.
A recent report by Politico detailed a blowup that Mr. Epshteyn had with Fox News, the cable network that most consistently defends the president’s agenda.
Mr. Epshteyn, known for his argumentative, badgering style on TV, was a spokesman for the presidential inaugural committee.