The White House now says that adding a prescription drug benefit to Medicare will actually cost $134 billion more than first estimated.
When President Bush signed the benefit two months ago his aides had said it would cost $400 billion, the Washington Post reported Friday.
But the budget Bush will submit to Congress on Monday says it will require $534 billion in the next decade, a third more than first estimated, according to congressional and administration sources.
News of the extra cost raised the prospect that lawmakers would try to change major aspects of the Medicare law.
This is a work in progress, said Rep. Jack Kingston, R-Ga., a conservative who voted for the law.
When the measure squeaked through Congress, most Democrats argued that the law would provide skimpy drug assistance, make too little effort to constrain drug prices, and provide a financial boon to pharmaceutical manufacturers and private health plans.
House conservatives also opposed it, criticizing it as a unaffordable expansion of one of the country's main entitlement programs, particularly at a time of record budget deficits.
Administration officials would not explain the precise reason for the discrepancy.
Copyright 2004 by United Press International