The Washington-based fund lowered its forecast for U.S. growth this year and 2011, predicting a "slow" rebound restrained by a lack of consumer spending.

Geithner's Outlook

Countries that rely on exports to help lift their economies must change policies or "global growth will slow and all of us will be worse off," U.S. Treasury Secretary Timothy F. Geithner said today in advance of this week's meeting in Washington of the IMF, World Bank and Group of 20 nations.

Global exchange-rates are a source of contention heading into the meetings.

"It is very important to see more progress by the major emerging economies to more flexible, more market-oriented exchange-rate systems," Geithner said at the Brookings Institution in Washington. "This is particularly important for those countries whose currencies are significantly undervalued."

Geithner said the "greatest risk to the world economy today is that the largest economies underachieve on growth."

Voter Discontent

The economy is a top issue for voters in the November congressional elections and polls show the public is increasingly skeptical of President Barack Obama's performance. His job approval over a three-day period that ended Oct. 4 was 45 percent, compared with 53 percent at the same time last year, according to a poll from Princeton, New Jersey-based Gallup Inc.

Economists at Goldman Sachs Group Inc. said the U.S. economy will be "fairly bad" or "very bad" over the next six to nine months.

"We see two main scenarios," analysts led by Jan Hatzius, the New York-based chief U.S. economist at the company, wrote in an e-mail to clients dated yesterday. "A fairly bad one in which the economy grows at a 1 1/2 percent to 2 percent rate through the middle of next year and the unemployment rate rises moderately to 10 percent, and a very bad one in which the economy returns to an outright recession."

Hatzius placed the odds of a renewed recession at 25 percent to 30 percent, up from 15 percent to 20 percent at the start of the year.