With money pouring into the treasury and expanding the budget surplus, President Clinton said Tuesday he would be willing to talk about tax cuts next year after Congress fixes the Social Security system.

The president opened the tax-cut door a crack as he reported that the expected surplus is likely to hit $39 billion this year. The windfall already has whipped up tax-cutting fever on Capitol Hill."Let me be clear," Clinton said. "I will oppose any budget that fails to set aside the surpluses until we have strengthened Social Security for the 21st century.

"Let me also be clear that does not mean that in the future there could never be a tax cut," the president added. "It simply means that we need to know how we're going to pay for the challenges of reforming Social Security."

He said he hoped a solution could be found early next year.

Just five months ago, Clinton predicted a deficit of $22 billion for the fiscal year that ends Sept. 30. However, a torrent of money has been pouring into the treasury thanks to the strong economy, leaving economists scrambling to update their forecasts.

"This is, of course, very good news for the American people," the president said. "Now it's official that this year, well ahead of the most ambitious schedule, America has balanced the budget."

One of the most closely watched numbers is the five-year budget estimate. The latest projection is that the surplus will total $495 from 1999 to 2003. That is more than twice the estimate in February, $230 billion.

The administration says its estimates, which trail behind some predictions, are conservative.

The surplus would be the first since 1969.