AAP

Gold fell as US equities and the dollar firmed ahead of the outcome of congressional elections in the United States, denting the precious metal's appeal.

Oil prices have fallen further, with US crude futures sliding to an eight-month low, a day after Washington granted sanction waivers to top buyers of Iranian oil and as Iran said it had so far been able to sell as much oil as it needs to sell.

Wall Street's major indexes have closed higher as voters headed to the polls in US midterm congressional elections and investors hoped the result would provide some relief for stocks after prolonged uncertainty.

The Australian share market closed nearly one per cent higher after strong gains from banking, energy and resources stocks.

BHP Billiton's rail operations in the Pilbara are expected to be out of action for a week after a runaway train laden with iron ore travelled 92 kilometres with no-one on board before it was deliberately derailed.

The death of an electrician, who was crushed between a lift car and the shaft at an alumina refinery in the state's south, has led to South32 being fined $65,000.

The Australian share market has bolted out of the chute, climbing higher at the open with broad-based gains.

Oil prices were mixed after a steep five-day fall, as the United States formally imposed punitive sanctions on Iran but granted eight countries temporary waivers allowing them to keep buying oil from the Islamic Republic.

The S&P 500 has risen with boosts from financial, energy and defensive sectors as investors showed some caution on the eve of US congressional elections.

Gold inched lower as investors took some profits following a recent rally, but the metal traded within a narrow range as caution set in ahead of the US congressional elections.

A runaway train loaded with iron ore travelled with no-one on board for 92 kilometres in Western Australia's Pilbara region before it was deliberately derailed.

The Australian share market has closed lower following a weak lead from Wall Street with energy and healthcare stocks remaining in the red.

Westpac has reported a flat full-year profit of $8.07 billion after customer compensation and legal costs contributed to a weak second half at its consumer and wealth divisions.

Backpackers and other visitors on working holidays will be able to stay in Australia longer under a federal government plan to help farmers fill job shortages.

There was little lead from Wall Street as Australian shares dipped at the start of a new trading week, with energy, healthcare, and telco stocks sapping the local bourse in early trade.

Concerns that a trade deal between the United States and China may not be imminent have reined in a rally in world equity markets and reversed gains on Wall Street.

Oil prices have fallen about one per cent and notched a weekly loss of over six per cent, as investors worried about oversupply after the United States said it will temporarily spare eight jurisdictions from Iran-related sanctions.

Gold has slipped as the US dollar regained some ground on the back of strong American jobs data, putting the metal on track for its first weekly loss in five weeks.

The federal government expects to raise $6 billion over the next decade from changes to the taxation of Australia's big oil and gas producers.

A late rally from mining and health care stocks has lifted the Australian share market into the black despite energy shares and the big four banks dragging on the index.

Macquarie Group has lifted first-half profit 5.0 per cent to $1.31 billion, helped by increased mortgage lending and its involvement in the NSW government's part privatisation of WestConnex.

Australian shares have fallen at the open despite overnight gains on Wall Street, with energy stocks slipping on falling oil prices, and the financial sector also dragging on the bourse.

Gold rose nearly 2.0 per cent overnight, bouncing off a three-week low touched in the previous session as the dollar fell sharply from recent highs, making the metal cheaper for holders of other currencies.

Oil has fallen nearly 3.0 per cent, with US crude futures hitting lows not seen since April, due to growing concerns that global demand is weakening at a time when output from the world's major oil producers is surging.

US stocks have risen for a third straight session as President Donald Trump said trade talks with China were "moving along nicely," reviving hopes that the two countries can resolve their trade dispute.

On the first day of November the Australian share market drew inspiration from the spring carnival - it jumped, fell behind but sensed the winning post and surged clear to close higher, lifted by banking and mining stocks.

NAB's full-year profit has dropped 14.2 per cent to $5.7 billion after the lender booked more than $1.1 billion in restructuring costs and customer remediation.

BHP shares have jumped more than 4 per cent after the mining giant said it would return $US10.4 billion ($A14.7 billion) to shareholders in the form of an off-market buyback and special dividend.

Australian shares are ahead at the open following overnight gains on Wall Street and a five per cent surge in BHP after the mining giant announced it would return $14.7 billion to shareholders.

Gold has fallen to a near three-week low as the US dollar scaled a 16-month peak and a stock market rebound stirred renewed appetite for riskier

Oil prices have fallen and posted the worst monthly performance since mid-2016 on evidence of rising global crude supply, but losses were limited by signs of strong US demand for fuel.

A late surge from heavyweight banking, mining and energy stocks has pulled the Australian share market higher on a choppy trading day.