BOSTON/WASHINGTON (Reuters) - A newly fraying relationship between U.S. President Donald Trump and top White House economic adviser Gary Cohn has raised questions about how long Cohn will stay in his job, say two people with close ties to the White House. Several sources said Cohn, director of the National Economic Council, had long planned to stay in his post for at least a year. But one source said concern had grown among Cohn’s allies over the past 24 hours that he might be pressured to leave.  The recent concerns stem from a report in the Wall Street Journal – confirmed by other news media, including Reuters – that Cohn was unlikely to be nominated by Trump as a potential successor to Fed Chair Janet Yellen. Trump had mentioned Cohn in July for the job. Cohn resigned as president of Goldman Sachs to join the new administration. “The calculus has shifted for Gary. He’s gone, essentially, from untouchable to possibly being bounced out,” the source said. “The message is clear that suddenly Cohn’s job in the White House has real downside risk.” Cohn crossed Trump last month when he criticized the president in a Financial Times interview for his response to the violence at a rally organized by white nationalists in Charlottesville, Virginia, in which one woman died. One source close to the White House said Trump wanted to fire Cohn. “Hates him. But that could be ephemeral,” the source said. Cohn, who is Jewish, told the newspaper the administration “must do better” in condemning neo-Nazis and white supremacists.  The former investment banker gave the interview after his wife and daughters pushed him to speak out, if not quit, after Trump blamed “both sides” for the violence. Trump said there were “very fine people” among the white supremacist groups, a comment that disgusted Cohn and those close to him, people who know him said. While the interview was intended to signal that Cohn had no plans to leave the White House and planned to push ahead with his signature project, tax reform, sources said the comments upset Trump. Trump has gone hot and cold on other advisers, some of whom have stayed, while others have left. “Relationships change,” said a third source with close ties to the White House. “If Gary sticks around, I fully expect that Gary’s relationship with the president will improve.” People who know Cohn say that when he does leave the White House, he wants it to be on his own terms. A White House official said Cohn was focused on his job, especially tax reform. “Gary is focused on his responsibilities as the director of the National Economic Council, including a once-in-a-lifetime opportunity to deliver meaningful tax reform that creates jobs and grows the economy,” the official said. Cohn said in a CNBC interview last week he had a “great relationship” with Trump and the two were working well together.  