* ASX benchmark posts biggest intraday pct fall since Aug 5
* Ampol slumps on stake sale in convenience stores property trust
* NZ benchmark index posts best intraday pct gain since June 25
By Pranav A K
Aug 17 (Reuters) - Australian shares fell on Monday as the country's second-most populous state reported its deadliest day of the COVID-19 pandemic, with financial stocks leading the retreat.
The S&P/ASX 200 index .AXJO was down 0.9% to 6,073.10 by 0108 GMT in its biggest intraday percentage drop since Aug. 5. Last week, it gained 2%.
Victoria state, which extended the state of emergency by four more weeks on Sunday, reported its biggest daily death toll on Monday with 25 fatalities and 282 new infections. heavyweight financials .AXFJ dropped 1.7% and led declines on the benchmark. The "Big Four" banks lost between 1.1% and 2.3%.
Among other losers, mid-sized lender Bendigo and Adelaide Bank BEN.AX lost 5.6% and was headed for its worst day in more than two months as its annual profit nearly halved. Ltd ALD.AX slid 4% after Australia's biggest fuel supplier said it would sell a 49% stake in a convenience stores property trust to Singaporean sovereign wealth fund GIC GIC.UL and Charter Hall Group CHC.AX for A$682 million. stocks .AXIJ fell 1.1%, with EML Payments Ltd EML.AX and Computershare Ltd CPU.AX losing 2.6% and 2.3%, respectively.
New Zealand's benchmark S&P/NZX 50 index .NZ50 advanced 1.1% to 11,576.15 in its biggest intraday percentage gain since June 25.
Retirement village operator Summerset Group Holdings SNZ.AX was the biggest boost to the benchmark, despite a 6% fall in half-year profit.
New Zealand's prime minister, Jacinda Ardern, postponed the country's general election by a month to Oct. 19 as the city of Auckland remains in lockdown due to a new outbreak of the coronavirus.