The S&P 500 and Nasdaq powered to fresh records on Thursday after the Federal Reserve cut interest rates, extending a buoyant post-election rally.

While the Dow finished essentially flat, both the S&P 500 and Nasdaq jumped to new all-time highs, with large tech companies like Facebook parent Meta and Apple surging.

The Nasdaq Composite gained 1.51 percent, to 19,269. The Dow Jones Industrial Average was largely unchanged at 43,729, but the S&P 500 gained 0.74 percent, to 5,973.

The Fed shrugged off concerns about the impact of Donald Trump's election victory and moved ahead with a quarter point interest rate cut.

"In the near term, the election will have no effects on our policy decisions," Fed Chair Jerome Powell told reporters, noting there was still uncertainty about what President-elect Trump's actual economic agenda would be.

"We don't guess, we don't speculate, and we don't assume," he said.

All three major indices had earlier hit all-time highs on Wednesday as markets greeted Trump's election win in anticipation that tax cuts and the de-regulation would offset the impact of higher tariffs.

Markets were cheered by Powell's tone, which kept the door open to further interest rate cuts.

"Of course, there's going to be a debate about the pace of rate cuts, but policy makers and chair Powell mentioned that they continue to think that policy is restrictive," said Angelo Kourkafas, senior investment strategist at Edward Jones.

While tech shares advanced, banking shares pulled back after a torrid session on Wednesday. Bank of America dropped 1.4 percent, while JPMorgan Chase fell 4.3 percent. (AFP)