Aussie shares buoyed by trade surplus; a2 Milk and Spark lead NZ

* Market boosted by bigger-than-expected trade surplus

* Financials lead gains(Updates to close)

March 8 (Reuters) - Australian shares rose on Thursday,buoyed by positive sentiment after January's trade surplushandsomely topped expectations.

The S&P/ASX 200 index rose 0.69 percent, or 40.9points, to 5,942.9 by the end of trade. The benchmark dropped 1percent in the previous session.

Australia posted a seasonally adjusted trade surplus ofA$1.06 billion ($828.6 million) in January, beating a Reutersforecast of A$300 million, and in sharp contrast to December'sA$1.36 billion deficit.

Financial stocks spearheaded gains, ending 0.78percent higher, with the 'Big Four' banks rising from 0.5percent to 1.4 percent.

Commonwealth Bank of Australia was the biggestboost on the benchmark, ending up by 1.4 percent.

Biotherapeutics developer CSL ended 1.3 percenthigher and online job portal Seek Ltd climbed about 3percent.

Materials stocks were the only losers on S&P/ASX 200, with the metals and mining index falling by 0.6percent after the United States said it would slap heavy tariffson imported steel and aluminium.

Shanghai rebar steel futures fell for a fifth session onThursday to touch their lowest in almost two weeks. ShanghaiFutures Exchange rebar futures were down 1.7 percent at3,873 yuan ($612) a tonne by 0227 GMT

Iron ore prices on the Dalian Commodity Exchangefell as far as 510.50 yuan per tonne, the lowest since Feb. 2

Mining heavyweight BHP Billiton was the biggestdrag on the benchmark, falling for a second consecutive sessionand ending 2.04 percent lower.

South32 Ltd followed, ending 1.57 percent lower.

Across the Tasman Sea, New Zealand's benchmark S&P/NZX 50index rose 0.9 percent or 74.36 points to finish thesession at 8,358.70.

Consumer staples led the gains with a2 Milk Company Ltdending nearly 5 percent higher.

Telecommunications operator Spark New Zealand Ltdended 1.62 percent higher.

(Reporting by Syed Saif Hussain Naqvi in BengaluruEditing by Eric Meijer)