Mitt Romney has conceded that secretly filmed comments he made at a private fundraising event did "real damage" to his presidential campaign.

In his first television interview since November's loss, Mr Romney said that until late on election day, he believed he was going to defeat Barack Obama.

He said he regretted his wording in secretly recorded remarks at a Florida fundraiser about the "47 per cent" of Americans who were dependent on government and would never vote for him.

"It's not what I meant. I didn't express myself as I wished I would have," Mr Romney told the Fox News Sunday program.

"When you speak in private you don't spend as much time thinking about how something could be twisted and distorted, and it could come out wrong and be used.

"That hurt. There's no question that hurt and did real damage to my campaign."

Mr Romney also levelled a fresh blast of criticism at the US president for putting politics ahead of results in the confrontation with congressional Republicans over the budget and spending cuts.

"It kills me not to be there, not to be in the White House doing what needs to be done," he said in the interview.

"I don't see that kind of leadership happening right now.

"The hardest thing about losing is watching this critical moment, this golden moment slip away with politics."

He said his failing to appeal to minority voters was a "real mistake".

Mr Romney, who called for the "self-deportation" of illegal immigrants during the Republican primaries, lost the vote of more than seven of every 10 Hispanics to Mr Obama.

'Rollercoaster ride'

In the interview, Mr Romney mostly avoided questions about the heavy criticism he received from fellow Republicans for running a lacklustre and gaffe-prone campaign.

"It's like riding on a rollercoaster, exciting and thrilling and ups and downs but the ride ends and then you get off," he said, adding he would not run again but he would still be active in public life.

"It's not like can we be on a rollercoaster for the rest of our life. That ride's over."

Mr Romney said he was convinced he was headed to victory in November until early on election night, when he saw the first exit polls showing a tight race in Florida, where he expected to do well.

He said when "disappointing" results began to come in from Ohio, he knew it was over.

The interview was the first step in a slow public re-entry for the former Massachusetts governor who has been largely secluded at his southern California home with his wife Ann since the loss.

In two weeks, Mr Romney will make his first public speech since the election to a conference of conservative activists in Washington.

ABC/Reuters