US stocks finished mixed on Friday, reversing some earlier gains to close out a gloomy month of trading ahead of a likely government shutdown starting this weekend.

The United States is headed towards its first shutdown since 2019 on Saturday night, with hardline Republicans on Friday tanking a plan proposed by their own party to keep funds flowing.

Congress has also been trying to resolve a broader deadlock over calls for deep spending cuts.

The Dow Jones finished down 0.5 percent at 33,507, while the S&P 500 ended the day down 0.3 percent 4,288.

The Nasdaq eked out a small gain, climbing 0.1 percent to 13,219.

"I think the idea of a potential government shutdown is not a major factor driving stock prices but it certainly doesn't help sentiment at all," said Steve Sosnick from Interactive Brokers.

All three major stock indexes ended the month in the red, as investors digested the likelihood of interest rates remaining higher for longer in the Federal Reserve's long-running battle against inflation.

The Fed has raised interest rates 11 times in 18 months, but inflation is still stuck stubbornly above its long-term target of two percent.

Earlier on Friday, fresh data pointed to a slight uptick in the Fed's preferred measure of inflation – the personal consumption expenditures price index – due to rising petrol and food prices.

But excluding those two volatile items, so-called "core" inflation slowed markedly, providing the central bank with some good news as it weighs its next rate decision.

Among individual stocks, sporting goods company Nike saw its share price rise 6.7 percent after beating earnings expectations. (AFP)