"We've got roads and bridges across this country that need rebuilding," Obama, 50, said. "We've got more than 1 million unemployed construction workers ready to get dirty right now. There is work to be done and there are workers ready to do it. Labor's on board, business is on board. We just need Congress to get on board."

Republican Resistance

The discussions about making bigger moves on taxes amount to recognition by Obama's political advisers that billions of dollars in new infrastructure spending stands little chance of winning approval from the Republican-controlled House, the person said.

The person didn't give details of what specific tax measures Obama is considering. The president has repeatedly called for an extension of the 2 percent employee payroll tax holiday that Congress passed last year and will expire in December.

His aides have said he is considering a reduction in the employer portion of the payroll tax and proposals to reward businesses for hiring unemployed workers.

'Wait And See'

House Republicans haven't embraced the idea of a payroll tax holiday extension, with some lawmakers questioning its impact on long-term economic growth. Brendan Buck, a spokesman for Speaker John Boehner, an Ohio Republican, said "we'll wait and see what the president is offering, but we hope it represents a break from the costly, ineffective policies of the last few years."

House Budget Committee Chairman Paul Ryan, a Wisconsin Republican, and Ways and Means Committee Chairman Dave Camp, a Michigan Republican, have called for lowering the top individual income tax rate to 25 percent from 35 percent. Neither lawmaker has specified how they would achieve such a reduction. A major reworking of the tax code is unlikely before the end of the year.

Concern over the economy has increased as growth weakened during the first half of the year to its slowest pace of the recovery. U.S. stock futures fell, indicating that the Standard & Poor's 500 Index may slide for a third day when trading reopens today.

Treasuries rose, pushing 10-year yields to a record low as demand increased for the relative safety of government debt. Benchmark 10-year rates dropped eight basis points to 1.91 percent as of 9:17 a.m. in Tokyo, according to Bloomberg Bond Trader prices. The 2.125 percent note maturing in August 2021 rose 22/32, or $6.88 per $1,000 face amount, to 101 30/32.