In unusually blunt and combative language, the Senate's top Republican says White House offers to cut long-term spending amount to "smoke and mirrors" and directly challenged President Barack Obama's leadership in debt limit negotiations.

President Barack Obama warned Monday there would be no deal on raising the government's debt limit if Republicans don't compromise and said he would not sign a short-term extension — raising the stakes on volatile negotiations with the clock ticking toward a Aug. 2 deadline.

With the clock ticking toward an Aug. 2 deadline, congressional leaders return to the White House Monday for another round of budget bargaining with President Barack Obama, who has warned top lawmakers he will call daily meetings until they break their partisan stalemate.

President Barack Obama declared a debt-crisis session Thursday with congressional leaders was "very constructive" but said the parties were still far apart on deficit reduction proposals. He said he would reconvene the negotiators on Sunday.

President Barack Obama is pressing Democrats to support a higher deficit reduction proposal that could win Republican support for new tax revenue while reducing costs for major benefit programs such as Medicare and Social Security as the price to reach a deal on raising the government's debt limit.

Treasury Secretary Timothy Geithner offered a bullish assessment Tuesday of the chances of success for Vice President Joe Biden and a bipartisan band of lawmakers trying to craft a deal to slash the federal budget and raise the debt limit.

In an otherwise lean budget year, the House on Tuesday overwhelmingly voted to boost funding to take care of the medical needs of the nation's veterans.

Democrats controlling the Senate are vowing that any deal this summer to cut the deficit won't cut back benefits for people enrolled in Medicare.