Negotiations on raising the U.S. debt ceiling continue.

President Obama says progress is being made on a deal to raise the nation's debt ceiling.

Treasury Secretary Timothy Geithner agrees.

"Despite what you hear, and this is a complicated place, Washington, people are moving closer together," Geithner said Monday.

To emphasize their differences with Democrats, Republicans want to pass a balanced budget amendment and spending cuts without tax hikes.

President Obama has vowed a veto, frustrating conservatives.

Stock markets dropped and gold rose Monday, a sign investors fear default is possible.

Billionaire Warren Buffett sent Washington a message.

"You're running a totally unnecessary risk and you're sending a signal to the rest of the world that we really can't think ahead in this country," the Berkshire Hathaway chairman warned.

There is a backup plan.

Republicans are considering a move that would let the president hike the debt ceiling unilaterally, but that would mean no big plan to tackle the deficit.