Sept 20 (Reuters) - Australian shares rose more than 1% on Tuesday, driven by gains in financial and commodity stocks, even as investors braced for a likely hefty U.S. Federal Reserve rate hike this week.

The S&P/ASX 200 index had gained about 1.2% to 6,796.8 by 0045 GMT, with all sectors except healthcare trading in positive territory. The benchmark fell 0.3% on Monday.

Stock markets across the globe remained on edge amid expectations the Fed would keep its aggressive tightening path until next year to contain stubbornly high inflation.

Markets are pricing in a 75-basis-point hike, with futures showing an 18% chance of a full percentage point increase on Wednesday, according to CME's FedWatch Tool.

In Australia, the resources-rich bourse was led higher by miners despite volatile iron ore prices in China. The mining index rose as much as 2.2%, with sector leaders Rio Tinto and BHP Group firming 1.5% and 1.7% respectively.

Meanwhile, Fortescue Metals said it would spend about $6.2 billion to eliminate the use of fossil fuels and achieve "real zero terrestrial emissions" across its iron ore operations by the end of the decade.

The financial sector climbed about 1.4%, with the "big four" banks rising between 1.4% and 2.1%.

Energy stocks firmed 1.4%, as oil prices rose on worries of tight supplies outweighing fears that global demand could slow.

Index heavyweights Woodside Energy and Santos rose 1.1% and 1.3%, respectively.

New Zealand's benchmark S&P/NZX 50 index rose about 0.3% to 11,575.1.

(Reporting by Archishma Iyer in Bengaluru; Editing by Subhranshu Sahu)