The Australian share market has opened lower after the major banks lost much of their previous day’s gains following NAB’s first-half profit announcement.

The benchmark S&P/ASX200 index was down 45.4 points, or 0.71 per cent, to 6,330.5 points at 1030 AEST on Thursday, while the broader All Ordinaries was down 42.9 points, or 0.66 per cent, to 6,423.6.

The heavyweight financial sector led losses at the start of trade, collectively falling 1.40 per cent.

ANZ was down 2.58 per cent to $27.23, Commonwealth was down 0.86 per cent to $74.85 and Westpac was down 2.10 per cent to $27.55.

National Australia Bank, which cut its interim dividend by 16 per cent after posting a first-half cash profit of $2.95 billion, was down 1.03 per cent to $25.515.

AMP was down more than 4.50 per cent ahead of a possible second strike on executive pay at the wealth manager’s annual general meeting on Thursday.

The energy sector recorded the second-largest losses, dropping 1.09 per cent as a whole.

Santos, Woodside Petroleum, Oil Search and Beach Energy were down between 0.99 per cent and 2.08 per cent.

Elsewhere, Kidman Resources soared 42.25 per cent to $1.835 after Wesfarmers announced a $1.90 cash per share bid for the lithium company.

Woolworths was up 1.35 per cent to $32.40 after lifting third-quarter grocery sales by 4.2 per cent.

The local currency slumped against the US dollar early on Thursday morning after the Federal Reserve held interest rates steady and indicated there would be no change either way any time soon.

The Aussie dollar is buying 70.16 US cents, from 70.49 US cents on Wednesday.