NEW YORK (AFP) - Wall Street stocks dipped early Thursday, retreating a bit from records set in the prior session fueled by continued optimism about economic growth policies under President Donald Trump.

Analysts said the pause was not surprising after the Dow piled on 1.5 per cent Wednesday to close above 21,000 points for the first time. That record followed positive reviews of Mr Trump's speech to Congress Tuesday night outlining policy priorities, despite giving few details.

Markets also were gearing up for the first trades in vanishing-message company Snapchat after an initial public offering on Wednesday priced at US$17 per share to raise US$3.4 billion.

About 15 minutes into trading, the Dow Jones Industrial Average stood at 21,114.41, down a hair. The broad-based S&P 500 had slipped 0.2 per cent to 2,391.89, while the tech-rich Nasdaq Composite Index shed 0.1 per cent to 5,895.85.

Optimism that Mr Trump and congressional Republicans will enact tax cuts has fueled a major market rally since election day. US economic data has also improved.