Crude oil prices plunged 4.5% to $US90.78 ($NZ111) and spot gold prices fell 1.8% to $US1521.20, while in the United States the market downturn catalyst was provided by its central bank, the Federal Reserve, which lowered predictions for economic growth and employment during the next 18 months.
The combination of the IEA's move, negative US data and recent decision of the Organisation of Petroleum Exporting Countries not to increase its output, is casting a pall across expectations of a global economic recovery, the brokers said.
Markets were taken by surprise when the Paris-based International Energy Agency (IEA) announced it would make 60 million barrels of oil available during the next 30 days; half of which will come from the United States' 727 million-barrel Strategic Petroleum Reserve which has not been called on to do so since oil hit a record $US147 in July 2008.
The 60 million barrels is to replace the disruption of Libyan oil supplies, which produced about 1.2 million barrels a day until the revolution and Western intervention began.
Craigs Investment Partners broker Peter McIntyre said US stocks had retraced some of the lows hit during the trading day on reports indebted Greece had forged a deal with the European Union and International Monetary Fund over its economic austerity plans; a key point to gaining the next, crucial, funding tranche from the two organisations.
Mr McIntyre said the US involvement in the IEA, providing about 30 million barrels, was "innovative" in trying to underpin and encourage some recovery in the global economy.
"It is a stimulus measure by the US, outside of fiscal and monetary policies", which Mr McIntyre understood the US had not done for several decades.
The move could be positive for New Zealand in that the strength of the New Zealand dollar against the greenback at present could see "some relief" flowing through petrol-pump prices.
Mr McIntyre said despite the positive Greek news, US investors remained "cautious" during the trading day, following the Federal Reserve's "tepid" economic remarks, weak US job news and declines in energy-sector stocks.
Forsyth Barr broker Suzanne Kinnaird said US stocks fell after the Federal Reserve lowered its predictions for US growth and employment.
"The US economy is now forecast to expand by between 2.7%-2.9% this year, down from forecasts ranging from 3.1%-3.3% in April," she said.
She noted that the Dow Jones index earlier on was down 235 points to 11,874, but retraced some losses during the trading day to only finish down 59 points; or -0.9%.
The wider European Stoxx Europe 600 Index fell 1.4% after European Central Bank president Jean-Claude Trichet said the region's debt crisis was a threat to banks, with stocks in Spain's second-largest bank down 5.5% and Italy's Banca Monte dei Paschi di Siena down 5.1%.
"Energy shares also slumped following a plunge in crude prices after the International Energy Agency said it will release 60 million barrels of oil from emergency stockpiles," she said.
Spot gold prices fell 2% on Thursday, its biggest one-day drop in more than a month, after disappointing US jobless claims data hit investor risk appetite and boosted the US dollar,pummelling commodity and stock markets.
Investors sold gold to cover steep losses in the equity, grains and crude oil markets, which sank on news of the release of emergency oil reserves by the IEA, Reuters reported yesterday.
Michael Lynch, president of Strategic Energy & Economic Research, said the month-long oil release would probably depress prices temporarily, but was doubtful it would have a long-term impact.
"It creates an immediate [oil] glut. But they're not solving the problem."
If oil demand continued to rise to historic levels this year, oil suppliers would continue to have trouble keeping up, Mr Lynch said.
- Additional reporting The New Zealand Herald
