President-elect Donald Trump will not pursue a further investigation into Hillary Clinton's emails to help her "heal", his spokeswoman has said.
Senior Trump adviser Kellyanne Conway said he would back down from his pledge to appoint a special prosecutor to look into the former Secretary of State.
Mr Trump had threatened to "jail" Mrs Clinton, and at his rallies his supporters often chanted "Lock her up!"
FBI Director James Comey cleared Mrs Clinton of any wrongdoing.
Ms Conway told MSNBC morning show host Joe Scarborough: "I think when the president-elect, who's also the head of your party now, Joe, tells you before he's even inaugurated he doesn't wish to pursue these charges, it sends a very strong message - tone and content - to the members.
"And I think Hillary Clinton still has to face the fact that a majority of Americans don't find her to be honest or trustworthy, but if Donald Trump can help her heal, then perhaps that's a good thing," she added.
The right-wing Breitbart News Network, which aligned itself with the New York billionaire early in the election, swiftly decried the climbdown as a "broken promise".
During the second presidential debate in October, Mr Trump pledgedthat if elected, he would appoint a special prosecutor to look into Mrs Clinton's private email use, suggesting she would be prison.
The FBI director shook up the presidential race when he announced a new inquiry into her private email server shortly before the election, reviving an investigation that had been completed in July.