Wall Street stocks mostly rose on Tuesday ahead of key US inflation data and a hotly contested presidential debate.

Markets are eyeing Wednesday's consumer price index report, with the Federal Reserve having signaled a likely interest rate cut later this month in light of moderating inflation.

Investors are also anticipating the first, and perhaps only, debate between Vice President Kamala Harris and former President Donald Trump, which will take place Tuesday night in Philadelphia.

The debate "could potentially move the market a little bit but the uncertainty is not going to go away tonight," said Tom Cahill of Ventura Wealth Management.

The Dow Jones Industrial Average finished down 0.2 percent at 40,736.

The broad-based S&P 500 gained 0.5 percent to 5,495, while the tech-rich Nasdaq Composite Index gained 0.8 percent to 17,025.

The Dow's losers included JPMorgan Chase and Goldman Sachs, which dropped 5.2 percent and 4.4 percent, respectively following commentary about their banks' financial performance that disappointed investors.

Boeing was another weak link, falling 1.7 percent amid worries that a machinists union will reject a new contract with the company and vote to strike.

Apple declined 0.4 percent after the European Court of Justice ruled that the iPhone maker must pay US$14.3 billion in back-taxes to Ireland.

Oracle jumped 11.4 percent after reporting better than expected earnings. Revenues rose seven percent, boosted by gains in the cloud services business. (AFP)