Wall Street stocks finished mixed following a choppy session on Tuesday, as markets weighed the remaining risk of a US debt default following the White House deal with House Speaker Kevin McCarthy.

After rallying Friday in anticipation of an agreement, markets were muted as far-right Republicans in the House came out against the compromise.

"McCarthy still has some tricky math to get this through the House," said Art Hogan, an analyst at B. Riley Financial.

The Dow Jones Industrial Average finished 0.2 percent lower at 33,042.78.

The broad-based S&P 500 was flat at 4,205.52, while the tech-rich Nasdaq Composite Index gained 0.3 percent to 13,017.43.

Although investors' baseline assumption has been that the United States would avoid a default, markets have been pressured in recent weeks by rising fears that an agreement would not come in time.

"It won't take a lot to disrupt this debt deal, but optimism remains that Congress won't mess with putting the economy at risk of an unnecessary catastrophe," said Oanda's Edward Moya.

Data from the Conference Board showed US consumer confidence dipped in May, dragged down by a decline in how people perceive the job market.

The slight fall in consumer confidence will provide the Federal Reserve with a useful data point on how consumers view the economy as it mulls lifting interest rates again in order to control rising prices.

Among individual equities, chip company Nvidia gained 3.0 percent, leaving its valuation just under US$1 trillion after earlier topping the benchmark.

The surge in Nvidia shares comes amid rising confidence in new generative AI breakthroughs, capable of delivering the computing heft needed to churn out complex content in just seconds from data centres around the world. (AFP)