The benchmark S&P/ASX200 index on Wednesday finished down 4.6 points, or 0.06 per cent, to 8,309.4, while the broader All Ordinaries closed unchanged at 8,558.6.
The outcome of the Fed meeting will be announced in Australia's pre-dawn hours on Thursday.Â
While markets regard a rate cut as a foregone conclusion, Capital.com analyst Kyle Rodda predicted any year-end Santa rally would live or die on the central bank's commentary, guidance and projections for 2025.
Traders predict another half-point of US rate cuts in 2025 but persistent inflation risks could challenge that view, Mr Rodda said.
Four of the ASX's 11 sectors finished lower on Wednesday, six closed higher and energy ended flat.
The industrial sector was the biggest mover, climbing 0.8 per cent as Transurban rose 1.9 per cent and Computershare grew 1.8 per cent.
In the financial sector, Omni Bridgeway soared 50.3 per cent to an eight-month high of $1.45 after the litigation funder announced it would sell 70 per cent of its funds to US-based alternative investment manager Ares Management Corporation for $310 million.
The big four banks were mostly lower, with CBA down 0.9 per cent to $159.73, ANZ dipping 0.2 per cent to $29.36 and NAB dropping 0.5 per cent to $37.99 as the business-focused bank held its annual general meeting in Melbourne.
Westpac was the outlier, adding 0.6 per cent to $32.85.
In the heavyweight mining sector, BHP edged 0.1 per cent higher at $40.27, Rio Tinto was flat at $118.49 and Fortescue dropped 0.5 per cent to $18.57 per cent.
In health care, Clarity Pharma climbed 12.2 per cent to a one-week high of $5.17 after the radiopharmaceutical company announced it had developed a new product that could potentially target a range of cancer tumours.
On the flip side, Percheron Therapeutics plunged 88.1 per cent to an all-time low of 0.7 cents after a six-month Phase 2b clinical trial indicated its lead drug candidate was no better than a placebo in improving outcomes for non-ambulant boys with Duchenne muscular dystrophy.
"In the more rigorous environment of a randomised, placebo-controlled international study, avicursen has not performed in a way that we had been led to expect by earlier studies," Percheron chief executive James Garner said.
The Australian dollar had fallen to a fresh 13-month low against its US counterpart, buying 63.13 US cents, from 63.53 US cents at Tuesday's ASX close.
If it falls much further - below 62.69 US cents - the Aussie would be at a 26-month low against the greenback.
The domestic dollar was also at a four-and-a-half year low against the British pound.
ON THE ASX:
* The benchmark S&P/ASX200 index on Wednesday dropped 4.6 points, or 0.06 per cent, at 8,309.4
* The broader All Ordinaries was unchanged at 8,558.6.
CURRENCY SNAPSHOT:
One Australian dollar buys:
* 63.13 US cents, from 63.53 US cents at Tuesday's ASX close
* 96.84 Japanese yen, from 97.92 Japanese yen
* 60.11 euro cents, from 60.47 euro cents
* 49.70 British pence, from 50.12 pence
* 109.98 NZ cents, from 110.17 NZ cents
