Obama will also likely face questions on his decision to bring nearly 33,000 surge related troops home from Afghanistan by next summer in the session with reporters in the ornate East Room of the White House at 11.30 a.m. (1530 GMT).

He may also be under pressure to justify US involvement in the Libya campaign against Muamer Gaddafi after a bruising confrontation with Congress over the issue.

Talks on raising the US government's $14.29 trillion borrowing limit known as the debt ceiling have broken down, raising fears of no deal by an August 2 deadline which could force the United States into a damaging default.

Obama, who is dealing with the showdown as he cranks up his 2012 reelection campaign, met the top Democrat in the Senate Harry Reid and his Republican counterpart Senator Mitch McConnell Monday, but there was no sign of a deal. He will again meet Reid again along with Senate Democratic leaders later on Wednesday.

As political tensions rise, the White House has warned of "calamitous" consequences to the global economy if the talks do not seal an agreement and Washington is forced into default and runs out of money to pay its bills.

It accused Obama's Republican foes of siding with billionaires and private jet owners, and challenged the lawmakers to take on "some of their sacred cows."
But Republicans, who quit talks with the White House last week accusing Obama of pushing tax hikes, again demanded big spending cuts in return for agreeing to lift the debt limit.

In the United States, Congress has to agree to lifting the cap on government borrowing, and has done so repeatedly in recent years at the urging of successive Democratic and Republican presidents.

But this time, congressional Republicans elected last November in an anti-government backlash and on a platform of sweeping spending cuts, are demanding big concessions from the White House.

The White House says Republican budget plans would place the very survival of popular social entitlement programs like Medicare health plans for the elderly at risk.
Republicans claim Obama is motivated by preserving big government programs and wants tax increases which would harm the economy. They are demanding large cuts to the annual deficit, projected to hit $1.6 trillion this year.

The US government hit its legal borrowing limit on May 16 and a succession of meetings chaired by Vice President Joe Biden tried but failed to secure congressional approval to raise the ceiling.

The Treasury, which has performed a number of intricate financial measures since then, says it will run out of maneuvering room on August 2.

Financial rating agencies have warned of a possible downgrade of the top US debt rating without an increase in the debt ceiling.