President-elect Donald Trump has chosen South Carolina governor Nikki Haley as US ambassador to the United Nations, the first woman he has selected for a top-level administration post during his White House transition.
It will be a cabinet-level position, and Mrs Haley has accepted.
"Governor Haley has a proven track record of bringing people together, regardless of background or party affiliation, to move critical policies forward for the betterment of her state and our country," Mr Trump said. "She is also a proven deal-maker, and we look to be making plenty of deals. She will be a great leader representing us on the world stage."
Mrs Haley, an outspoken Trump critic throughout much of the presidential race, would become his first female - and first non-white - cabinet-level official if confirmed by the Senate.
She is the daughter of Indian immigrants and is the second Asian-American to serve as a US governor.
"Our country faces enormous challenges here at home and internationally, and I am honoured that the president-elect has asked me to join his team and serve the country we love as the next ambassador to the United Nations," Mrs Haley said.
Not all presidents have treated the ambassadorship to the UN as a Cabinet-level position, and Republicans have tended not to grant that status.
After secretary of state - a job Mr Trump has not yet filled - the ambassadorship is the highest-profile diplomatic position, often serving as the voice for US positions on the international stage. As part of the cabinet, Mrs Haley would have more opportunity to shape US policies, rather than simply defend the administration’s positions.
Yet it could be an awkward role at times. Mr Trump campaigned on the theme of "America first" and said he is sceptical about "international unions that tie us up and bring America down". Mr Trump has also described the United Nations as weak and incompetent.
Mrs Haley would be the third consecutive female US ambassador to the United Nations, after Susan Rice and Samantha Power, the current ambassador.
Mrs Haley’s new job clears the way for Lt Gov Henry McMaster to step into the role of South Carolina governor. Mr McMaster was an early Trump endorser, backing him before the state’s GOP primary in February.
At the time, Mrs Haley campaigned for Florida senator Marco Rubio, before going on to support Texas senator Ted Cruz.
Bad blood between Mr Trump and Mrs Haley was evident in interviews and on social media.
"The people of South Carolina are embarrassed by Nikki Haley!" Mr Trump wrote on Twitter in March, while Mrs Haley denounced several of Mr Trump’s campaign comments and urged voters to "reject the siren call of the angriest voices".
The people of South Carolina are embarrassed by Nikki Haley!— Donald J. Trump (@realDonaldTrump) March 1, 2016
Still, Mrs Haley met with the president-elect last week at Trump Tower. After, she said they had a "very nice" conversation.
A week ago while meeting with other Republican governors in Orlando, Mrs Haley described herself as "giddy" over the prospect of joining the Trump administration. She said she was heartened by his tone and inclusiveness after winning the election. "I hope he continues to do that, and I hope he continues to be disciplined in his comments."
Mr Trump is spending Thanksgiving with his family at his Mar-a-Lago estate in Palm Beach, Florida.
Earlier, Mr Trump offered a senior job to Republican rival Ben Carson and condemned the controversial alt-right movement on another busy day for the president-elect.
He also spoke positively about President Barack Obama and risked further angering some hardline supporters by signalling that he does not want defeated Democratic candidate Hillary Clinton to be prosecuted.
Mr Trump has officially asked Mr Carson to head the Department of Housing and Urban Development, and he is expected to respond after the holiday.
During an interview with the The New York Times, Mr Trump denied there could be conflicts due to a lack of separation between being president and his many businesses.
He said: "The law’s totally on my side, the president can’t have a conflict of interest."
Mr Trump took his strongest stance yet against the so-called "alt-right," a term often used as code for the white supremacist movement.
Though members are celebrating his victory, he said: "It’s not a group I want to energise. And if they are energised, I want to look into it and find out why."
The president-elect, who has been criticised for being slow to denounce racist acts done in his name, said "I disavow and condemn" a recent "alt-right" conference in Washington where some attendees raised their arms in a Hitler-like salute while chanting "Heil Trump".
But he defended the appointment of Stephen Bannon to a senior White House job. The former head of conservative news site Breitbart has links to the alt-right movement that have drawn widespread criticism from Democrats.
During the New York Times interview Mr Trump said President Obama is "looking to do absolutely the right thing for the country in terms of transition".
And he used to the interview to say: "I don’t want to hurt the Clintons, I really don’t." Sympathetically, he added: "She went through a lot and suffered greatly in many different ways."
Though he declined to definitively rule out a prosecution, he said: "It’s just not something that I feel very strongly about."
The comments stood in stark contrast to his incendiary rhetoric throughout the campaign, during which he accused Mrs Clinton of breaking the law with her email practices and angrily barked at her that "you’d be in jail" if he were president.
His adviser Kellyanne Conway said that Mr Trump "is "thinking of many different things as he prepares to become the president of the United States, and things that sound like the campaign aren’t among them".
Some of Mr Trump’s conservative supporters strongly disagreed.
The group Judicial Watch said if Mr Trump’s appointees do not follow through on his pledge to investigate Mrs Clinton for criminal violations he accused her of "it would be a betrayal of his promise to the American people to ’drain the swamp’ of out-of-control corruption in Washington".
And Breitbart headlined its story about the U-turn with "Broken Promise".
FBI Director James Comey has declared on two occasions there is no evidence warranting charges against Mrs Clinton.
Justice Department investigations are historically conducted without the influence or input of the White House.