* Materials and energy gain on higher commodity and oil prices
* Banks fall, offseting gains on the benchmark
* NZ index increases marginally
(Updates to close)
By Aditya Soni
Sept 26 (Reuters) - Australian shares rose fractionally on Wednesday as gains in materials and energy stocks on higher oil and commodity prices offset losses for banks as release of an inquiry's interim report on the sector nears.
The S&P/ASX 200 index .AXJO rose 0.1 percent or 6.4 points to end at 6,192.3 . On Tuesday, the benchmark slipped 1 point.
Dalian iron ore DCIOcv1 jumped 1.1 percent on Wednesday, boosting buying interest in materials stocks, accounting for most of Wednesday's gains on the benchmark.
The metals and mining index .AXMM climbed 1 percent to its highest since Aug. 10.
Both BHP BHP.AX and Rio Tinto (LON:RIO) Ltd RIO.AX firmed 1.2 percent, taking them to two-month highs.
Energy stocks also advanced, benefiting from a rally in oil prices. Brent crude futures LCOc1 were flat on Wednesday after gaining nearly 1 percent in the previous session.
Woodside Petroleum Ltd WPL.AX , the biggest listed oil and gas explorer, rose 1.5 percent to a near-four year high.
However, financials .AXFJ fell 0.6, erasing most of the benchmark's gain.
An interim report of the powerful Royal Commission inquiry into Australia's banking and financial services sector is due no later than Sept. 30.
Investors suspect the Royal Commission could hit the financial sector hard, which is affecting share movement before its release, said Greg McKenna, an independent financial analyst in Australia.
Commonwealth Bank of Australia CBA.AX , the biggest lender, fell 0.9 percent and was the major top drag on the index, while National Australia Bank Ltd NAB.AX slipped 0.5 percent.
In New Zealand, the benchmark S&P/NZX 50 index .NZ50 edged 3.89 points higher to finish the session at 9,349.85.
Gains were dominated by Fletcher Building Ltd FBU.NZ which rose 2.2 percent to a near four-week high.