Sept 12 (Reuters) - Australian shares fell on Tuesday, dragged by declines in heavyweight financials stocks, while cautious investors awaited a key U.S. inflation data later in the week for cues on the U.S. Federal Reserve's rate hike trajectory.

The S&P/ASX 200 index fell 0.4% to 7163.7 by 0127 GMT. The benchmark index closed 0.5% higher on Monday.

Financial stocks fell 0.8%, with the "Big Four" banks shedding between 0.5% and 0.7%.

Mining stocks led gains as they rose 0.2%, tracking copper and iron ore prices higher.

Sector majors BHP and Rio Tinto up 0.4% and 1.3%, respectively.

Copper prices rose on Monday in the face of a stronger Chinese currency and a weaker dollar, while iron ore prices rebounded as sentiment lifted on Beijing's pledge to step up regulatory oversight.

The gold sub-index increased 0.5%, with sector heavyweights St Barbara and Northern Star Resources climbing 1.4% and 0.8%, respectively.

Energy stocks lost 1.5%, which led losses on the benchmark, with sub-index majors Woodside Energy and Santos declining more than 1%, each.

In corporate news, Santos conducted a debt offering and successfuly priced a $850 million senior unsecured fixed rate bond.

Across the Tasman Sea, New Zealand's benchmark stock index fell 0.2% at 11,276.66, rebounding after declines on Monday.

(Reporting by Shivangi Lahiri in Bengaluru; Editing by Rashmi Aich)