* RBA is likely to hike rates by 50 bps - Reuters poll

* Most sub-indexes gain

* NZX 50 posts biggest pct gain in one week

July 4 (Reuters) - Australian shares climbed more than 1% on Monday after banks gained ahead of a possible half percentage-point rate hike by the Reserve Bank of Australia and as a jump in commodity stocks added support.

The S&P/ASX 200 index snapped three straight sessions of declines to end the session 1.1% higher. The benchmark slipped 0.4% on Friday.

A Reuters poll found that the RBA is likely to hike its cash rate by 50 basis points again when they meet on Tuesday to tame surging inflation, which hit a 20-year peak in the first quarter of this year.

Robust retail sales and very strong job vacancies data last week further strengthen the case for the central bank to move quickly away from emergency settings, NAB analysts said in a note

Rate-sensitive financial stocks climbed 0.9% to be among the top gainers, boosted by the "big four" banks.

Commonwealth Bank of Australia, National Australia Bank, Australia and New Zealand Banking Group and Westpac Banking Corp gained between 0.8% and 1.3%.

The gold index climbed 2.6% to record its best session since June 17, tracking prices of bullion.

Sector heavyweights Newcrest Mining Ltd and Northern Star Resources climbed 2.3% and 3.7%, respectively.

The energy index gained 2.6% as well, despite a fall in oil prices. However, supply concerns limited losses in crude prices.

Santos advanced 3.3%, followed by Woodside Energy Group, which closed 2.7% higher.

Miners closed 0.2% higher as Rio Tinto and Fortescue Metals climbed 0.4% each.

New Zealand's benchmark S&P/NZX 50 index rose 1% to finish the session at 10862.34 points.

(Reporting by Tejaswi Marthi in Bengaluru; Editing by Amy Caren Daniel)