Australian shares snapped three consecutive sessions of gains to end lower on Wednesday, as the benchmark tracked an overnight slump in Wall Street, with traders awaiting cues on interest rates from the US Federal Reserve's two-day policy meet.

The S&P/ASX 200 index fell 0.5% to finish at 6,795.20.

The benchmark ended 0.8% higher on Tuesday.

Fed policymakers are likely to forecast that the US economy will grow in 2021 at the fastest rate in decades, and reiterate their pledge to remain accommodative for the foreseeable future.

However, fears about an overheating economy and a jump-forward in interest rate expectations have increased scrutiny on the Fed meeting.

"They are in a very difficult position. If they get the policy wrong it may be very damaging to equity markets," said Brad Smoling, managing director at Smoling Stockbroking.

"My feeling is they will not be able to allow interest rates to rise much further."

Australian energy stocks closed 1.2% lower, after earlier marking its biggest percentage loss in a week, as the sector was hit by a fall in oil prices.

Oil Search declined nearly 3%, while Santos Ltd ended 1.2% lower.

Miners finished 1.4% weaker on lower copper prices, with global miners BHP Group and Rio Tinto each closing down over 1%.

The gold index snapped two sessions of gains to close 1.4% lower as bullion prices weakened against a stronger US dollar.

Medusa Mining and Dacian Gold closed down 6% and 5%, respectively.

Meanwhile, technology stocks mirrored an overnight rise in the tech-heavy Nasdaq index to climb 0.7%, marking its second straight day of gains. Afterpay ended over 1% higher, while WiseTech Global settled over 3% up.

New Zealand's benchmark S&P/NZX 50 index fell 0.5% to finish the session at 12,622.21.

Top losers were Sanford Ltd, shedding 7.6%, and Contact Energy losing 4.5%.