US President Barack Obama has invited congressional leaders to start negotiating a deal to prevent sharp tax hikes and spending cuts from going into effect at the end of the year.

He said he was open to new ideas in his first White House appearance since defeating Republican Mitt Romney in Tuesday's election.

"I'm committed to solving our fiscal challenges, but I refuse to accept any approach that isn't balanced," he said.

He again pushed for higher taxes for wealthier Americans.

If Congress and the administration do not act, the abrupt fiscal tightening would tip the weak economy into recession, analysts have said.

The nonpartisan Congressional Budget Office said this week unemployment could rise above 9% next year if nothing is done to avert the so-called fiscal cliff.

Emotional Obama thanks campaign workers

Earlier, a video of  Mr Obama was released showing him wiping away tears the day after his re-election as he thanked young members of his campaign team for their hard work.

In the video released by his campaign, Mr Obama told staff members: "I am absolutely confident that all of you are going to do just amazing things in your lives."

He was speaking at his Chicago headquarters on Wednesday following his victory over Mr Romney.

Mr Obama said the campaign team is "so much better" at meeting goals and in effectiveness than he had been as a young community organiser in Chicago.

Becoming emotional, Mr Obama said his work in running for office has come "full circle".

"Because what you guys have done means that the work I'm doing is important. And I'm really proud of that. I'm really proud of all of you," Mr Obama said, wiping away tears.

The workers responded with loud applause.

Mr Obama also became emotional in his final rally on Monday night in Iowa, as his voice broke and he wiped tears from his eyes as he reflected on those who had helped his campaign.