* Fortescue rises 3.5%, sees best day in over 2 weeks
* Big Four banks gain up to 0.8%
* Trading subdued ahead of public holiday
* NZ bourse snaps four straight gain sessions
Jan 25 (Reuters) - Australian shares opened higher on Monday, led by gains in miners and financials, while trading remained subdued ahead of a public holiday and a raft of economic data scheduled to be released during the week.
The S&P/ASX 200 index .AXJO rose 0.2% to 6,814.40 by 0000 GMT in a low volume session that saw just over 15% trades of the 30-day average of nearly 543 million shares.
The markets will be closed on Tuesday for Australia Day.
Over the week, investors will be eyeing domestic inflation data, U.S. Federal Reserve meeting, and fourth-quarter advanced economic growth data for the United States.
Australia's fourth-quarter headline inflation, to be released on Wednesday, is likely to remain unchanged from previous quarter, according to a Reuters poll.
Among gainers in the index, heavyweight miners .AXMM were the top gainers in the index, jumping nearly a percent.
Global miners BHP Group BHP.AX and Rio Tinto (LON:RIO) RIO.AX advanced up to 1.4% and 1.1%, respectively, while Fortescue Metals Group FMG.AX added up to 3.5%, marking its biggest intraday jump in over two weeks.
In financials .AXFJ , all 'Big Four' banks traded in the positive territory, with top lenders Commonwealth Bank of Australia CBA.AX and National Australia Bank NAB.AX adding up to 0.8% each.
Meanwhile, Australia approved the Pfizer/BioNTech COVID-19 vaccine for use under a formal process, with vaccination of priority groups expected to begin in late February. the gains, energy stocks .AXEJ were the top loser in the index, slipping as much as 1.7% in their third straight session of losses, as oil prices fell overnight on demand concerns following new pandemic restrictions in China. O/R
Blue-chip gas producers Woodside Petroleum WPL.AX and Santos STO.AX lost up to 1.3% and 0.9%, respectively.
In New Zealand, the benchmark S&P/NZX 50 .NZ50 slid 0.2% to 13,302.28, snapping four straight sessions of gains.
Healthcare and industrials were the top drags, offsetting gains made by financials.