The US must raise its US$14.3 trillion debt ceiling if it is to borrow beyond August 2 and be able to pay its bills.

But cross-party talks have so far failed to make a breakthrough and Mr Obama has warned time is running out.

Republicans have rejected the president's proposals to increase taxes on wealthier Americans to raise funds.

They say doing so would stifle investment and job growth.

Republicans, who control the House of Representatives, say they will not raise the debt limit unless Democrats agree to major spending cuts.

Mr Obama's spokesman Dan Pfeiffer said the president was discussing "various options" during private talks on July 16 with congressional leaders.

In his weekly national address, Mr Obama said all Americans had to play their part in resolving the crisis, saying: "We're all in this together."

"The truth is, you can't solve our deficit without cutting spending," he said.

"But you also can't solve it without asking the wealthiest Americans to pay their fair share - or without taking on loopholes that give special interests and big corporations tax breaks that middle-class Americans don't get."

Mr Obama has said he is prepared to enact cuts to benefits and welfare schemes, but would need Republicans to consider some revenue increases in return.