From my friends at the DNC:

Today, White House Press Secretary Dana Perino provided the Administration’s latest excuse for not working with Congressional Democrats to break the spending impasse. The facts are clear: The President has now twice rejected the Democrats’ unified spending plan. Perino claimed the White House would begin negotiating with Democrats “once they coalesce around one position.” But four days ago, the White House issued a veto threat on the Democratic spending bill – before it even saw it. Moreover, last month, the White House rejected overtures by Democratic leaders to reach an agreement on spending. The White House is making it clear they are more interested in a government shut down than working with Democrats to invest in the critical priorities of the American people. Below are Perino’s comments and the corresponding facts.

Today, White House Press Secretary Dana Perino Claimed the President Would Begin Negotiating With Democrats Once a Position on Spending Is Formed. Perino said, “It’s very difficult to negotiate when you’re dealing with several different positions on the Democratic side.  So once they coalesce around one position it will be easier for us to sit down and have the negotiations.” Later on her presentation, Perino said “they have to have a united position for us to react to.  It’s unreasonable for us to try to react to four different positions.” [White House Press Briefing, 12/12/07]

But on Saturday, the White House Said It Would Veto the Democratic Spending Package.
  In a statement, White House Budget Director Jim Nussle admitted the Administration “has not seen the legislation.” However, he claimed, “If presented a bill like the one described in today’s press reports, the President would veto it.” [OMB Press Release, 12/8/07]

Perino Also Claimed the White House Had an Open Dialogue With Congressional Leaders to Reach A Consensus on Spending.  Perino was asked, “So you can’t have a negotiation until you’re willing to talk?” To which she answered, “We are willing to talk. We have an open dialogue. And we have Director Nussle, who is speaking for the president, acting on behalf of the president, working with them.” [White House Press Briefing, 12/12/07]

But the White House Refused To Negotiate With Congressional Leaders on Spending. 
Trying to break a fiscal impasse with the White House, Congressional Democrats made an overture to the Administration in order to reduce the spending sought by Congress. However the administration quickly dismissed the move. “The president has been clear that Congress should adhere to the budgetary process and pass individual funding bills at reasonable and responsible spending levels,” said Sean Kevelighan, a spokesman for the Office of Management and Budget. [New York Times, 11/16/07]