In a far-ranging interview with the New York Times, the US president-elect was quoted as saying: "I condemn them. I disavow, and I condemn."

He said he did not want to "energise" the group, which includes neo-Nazis, white supremacists and anti-Semites.

One of America's top generals, David Petraeus, has told the BBC he would be willing to serve under Mr Trump.

The former CIA director, a prominent figure during the Obama era until he resigned in 2012 over an extramarital affair, said it was up to Americans to "endeavour to help" the incoming president.

Mr Trump, who is due to take over from Barack Obama on 20 January, is still assembling his White House team but has already courted controversy with some of his choices.

He has defended his chief strategist Steve Bannon, the former CEO of Breitbart News, bristling at claims that the ultra-conservative site is associated with white supremacists.

'Hail Trump'

Alt-right supporters were filmed on Saturday in Washington DC cheering as a speaker shouted: "Hail Trump."

In the video, Richard Spencer, an alt-right leader, told a conference that America belonged to white people, whom he described as "children of the sun".

He denounced the movement's critics as "the most despicable creatures who ever walked the planet".

"Hail Trump, hail our people, hail victory!" Mr Spencer shouted at one point as some members of the audience raised their arms in the Nazi salute.

The gathering on Saturday drew protesters who blocked traffic around the Ronald Reagan Building, a federally owned conference centre in the nation's capital.

German Chancellor Angela Merkel expressed concern on Tuesday that Mr Trump's election victory could give succour to white supremacists.

A senior official close to her described the "Hail Trump" video as "repulsive and worrying".
More on the alt-right

"Breitbart is just a publication," Mr Trump told the New York Times. "They cover stories like you cover stories."

"If I thought he was a racist or alt-right or any of the things, the terms we could use, I wouldn't even think about hiring him", he said of Mr Bannon.

Mr Trump also argued that:

    Son-in-law Jared Kushner - a real estate heir who has no experience of diplomacy - could help forge peace between Israel and Palestinians

Earlier on Tuesday, Mr Trump's spokeswoman said he would not follow up on a campaign pledge to pursue a further inquiry into Hillary Clinton's emails.

Later, Mr Trump was quoted as telling the New York Times: "I don't want to hurt the Clintons, I really don't."