* Aussie benchmark up to 4th session

* South Australia goes into 6-day lockdown

* Financial sub-index extends gains to 4th day

Nov 19 (Reuters) - Australian shares closed higher on Thursday, recouping early losses due to gains in financial stocks, while New Zealand extended falls from the previous session as worries over surging global COVID-19 cases dampened sentiment.

The S&P/ASX 200 index swung into positive territory in the last hour of trade after spending most of the session in the red, closing up 0.25% at 6,547.2 points.

U.S. stocks closed steeply lower after a late-session sell-off on Wednesday as investors weighed surging COVID-19 infections and mounting shutdowns against encouraging vaccine developments.

Adding to the risk-off mood, the state of South Australia went into strict lockdown on Thursday to stifle the latest cluster of 23 novel coronavirus infections.

A vaccine is further down the track compared to the current trend of soaring infections and restrictions hampering economic recovery, said James Tao, a market analyst at CommSec.

"The good news is kind of being pushed to one side at the moment," Tao said.

Financial stocks extended gains to a fourth day and hit their highest in more than eight months, with the "Big Four" banks climbing between 1.2% and 2.3%.

On the other side of the ledger, gold stocks touched their lowest in nearly five months, as optimism over the new vaccine dented the appeal of the safe-haven commodity.

Newcrest Mining closed down 2.6% while ASX-listed shares of AngloGold Ashanti shed 4.2%.

Miners shed 0.5% while energy stocks added 0.3%, helped by gains in Worley and Woodside Petroleum .

In New Zealand, the benchmark index closed 0.4% lower at 12,557.13 points. Tourism Holdings, down 3.7%, was the biggest percentage loser, followed by Serko Ltd , slipping 2%. (Reporting by Arundhati Dutta in Bengaluru; Editing by Ramakrishnan M.)