President Bush admitted Friday that "our economy has slowed," but said Americans could counter the downturn if they do one thing: spend.

Bush spoke to reporters at the White House in a hastily arranged appearance timed to Friday's release of a gloomy government economic report. He says the long-term outlook for the economy is good.

The president said, "Our economy will prosper."

Bush's top economic adviser said earlier that the nation's economic growth could dip into negative territory for the current quarter. That tracks with the assessments of many outside experts but is the most pessimistic word to come so far from the White House.

"We don't really know whether it will be negative or not," Edward Lazear, chairman of the White House Council of Economic Advisers, told reporters at the White House. "We have definitely downgraded our forecast for this quarter."

He would not discuss whether the White House is predicting the economy will actually fall into a recession. Some economists think it already has.

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"I'm still not saying that there's a recession," Lazear said. "We are going to have a weak growth quarter, and whether you call that a recession or not is something that we won't know for many months."

Still, the White House was eager to put a good face on the economic picture, clouded by the release earlier Friday of a report showing the economy lost 63,000 jobs last month, the most in five years. Shortly after Lazear appeared to speak to reporters, Bush was to make a hastily arranged statement on the economy at the White House.

Lazear said the White House predicts jobs numbers will pick up by spring and growth will rebound by summer, driven primarily by a recently passed stimulus package.

"This quarter will be our weakest quarter," he said. "There are indicators suggesting that growth will pick up and pick up quickly. So the question is how quickly will it pick up."

He highlighted what he said was the good news in Friday's jobs reports: that is showed that unemployment dipped, wages grew and weekly hours stayed the same. However, the jobless rate fell to 4.8 percent in February from 4.9 percent because so many people stopped looking for work and left the labor force. And average hourly earnings for jobholders rose only an anemic 0.3 percent from the previous month.