Dec 22 (Reuters) - Australian shares swung between positive and negative territory on Wednesday, as losses in banks and gold explorers countered gains made by miners and technology stocks. The S&P/ASX 200 index (.AXJO) was flat at 7,355.2 by 2344 GMT, after notching its best session in two weeks on Tuesday. The Australian central bank is optimistic that Omicron will not derail the country"s economic recovery, though the rapidly spreading coronavirus variant has rattled global equity markets in recent weeks. read more Technology stocks (.AXIJ) tracked Wall Street higher, rising as much as 1.8%. Buy now, pay later giant Afterpay (APT.AX) jumped 6.6% in its best intraday session since Aug. 3. Miners (.AXMM) advanced 0.4%, underpinned by strong iron ore prices. BHP Group (BHP.AX) said it would not match a takeover offer by billionaire Andrew Forrest"s Wyloo Metals for Noront Resources Ltd (NOT.V), essentially bowing out from a months-long tussle for the Canadian nickel miner. read more Meanwhile, Rio Tinto (RIO.AX) said it would buy the Rincon lithium project in Argentina for $825 million to build its battery materials business. Shares of the miner were down 0.8%. read more Healthcare stocks (.AXHJ) climbed, led by a 1.5% jump in biotechnology giant CSL Ltd . Energy stocks (.AXEJ) rose 0.9% on the back of firmer oil prices, with Whitehaven Coal (WHC.AX) and Paladin Energy (PDN.AX) adding 3.3% and 1.8% respectively. Heavyweight financials (.AXFJ) fell as much as 0.4%, with three of the so-called "Big Four" banks trading in negative territory. Weakness in gold prices weighed on the ASX-listed explorers of the metal, with Newcrest Mining (NCM.AX) and Northern Star Resources (NST.AX) both shedding more than 1%. New Zealand"s benchmark S&P/NZX 50 index (.NZ50) was down 0.5% at 12,798.19. On Tuesday, the country postponed its phased border re-opening plans until the end of February over concerns about the rapid global spread of the Omicron variant. read more Reporting by Harish Sridharan in Bengaluru; Editing by Subhranshu Sahu