* Aussie inflation, RBNZ rate decision key

* Australia's financial sub-index at 17-yr high

* Summerset Group, Goodman Property Trust top gainers on NZ50

Feb 26 (Reuters) - Australian shares ended the session marginally higher on Monday, as gains in financials and gold stocks countered the losses in heavyweight miners and energy firms, while traders remained cautious ahead of a key domestic inflation report this week.

The benchmark index S&P/ASX 200 ended up 0.1% at 7,652.80 points.

Investors were on their toes at the beginning of an inflation-focused week globally with key readings in the U.S., Europe, and Australia in focus. Additionally, New Zealand's central bank is set to unveil its monetary policy decision on Wednesday.

"I think the base case is that the RBNZ (Reserve Bank of New Zealand) will hold fire this week but by all accounts they are ready to pull the trigger for further tightening as needed," Tim Waterer, chief market analyst at KCM Trade, said.

Australia's inflation figures are expected to have "nudged modestly higher," which could potentially delay the timeline for interest rate cuts, Waterer added.

In Sydney, gold stocks gained 1.6%, marking their best day since Feb. 16, while banks added 0.6% to end at a record closing high since Dec. 2007.

Countering the gains, energy stocks dropped 2.1%, registering their worst day since early December, as oil prices extended losses amid concerns over a potentially higher U.S. inflation print.

Sector heavyweights Woodside and Santos fell 1.7% and 5.3%, respectively.

Miners followed suit, slipping 0.4% on the back of declining iron-ore and copper prices.

Separately, Alumina surged 6.9% following a $2.2 bln buyout bid from U.S. aluminium producer Alcoa in an all-stock offer.

Across the Tasman Sea, the New Zealand S&P/NZX 50 index fell 0.09% to 11,709.89 points.

Summerset Group and Goodman Property Trust topped gains on the benchmark, adding 3.4% and 2.6%, respectively.

The country's central bank is expected to cut rates in November, while holding its cash rate at a 15-year high of 5.50% on Wednesday, according to a Reuters poll. (Reporting by Roshan Thomas in Bengaluru; Editing by Dhanya Ann Thoppil)