A summary of trading in key commodities markets overseas:
World oil prices have finished lower in choppy trade as the strong dollar weighed and a potential rise in Iraq exports heightened global oversupply worries.
US benchmark West Texas Intermediate for delivery in July fell 52 cents to $US57.51 a barrel on the New York Mercantile Exchange on Wednesday.
Brent North Sea crude for July, the global benchmark, tumbled to $US62.06 a barrel in London trade, down $US1.66 from Tuesday's settlement.
The market pulled up in early trade but gains evaporated as the dollar strengthened slightly, touching its highest level in nearly a month against other major currencies, making dollar-priced crude oil more expensive.
The market may be undergoing "a bit of book squaring ahead of US petroleum inventory data", said Tim Evans of Citi Futures.
The Department of Energy's weekly petroleum report, usually released on Wednesdays, will be issued on Thursday due to a public holiday on Monday.
Analysts expect that crude inventories fell for a fourth consecutive week, by 2.0 million barrels, according to a survey by Bloomberg News. The stockpiles currently stand at 482.2 million barrels, just below their highest levels on record.
Traders have been hoping that a slowdown in US output, coupled with increased demand during the summer driving season, could ease the global oversupply, a key factor in driving prices of more than 50 per cent between last June and January.
Concerns about a potential rise in Iraqi oil exports also cast a cloud over the supply outlook, Commerzbank said.
"Iraq may flood the oil market with additional oil next month: according to shipping programs, Iraqi oil exports are set to soar by 800,000 barrels per day month-on-month and achieve a new record level of 3.75 million barrels per day," the German bank said in a research note.
"If this actually comes to pass, the oversupply risks becoming even bigger."
Gold prices were steady after initially falling to a two-week low as the US dollar retreated from a one-month high.
However, the precious metal is still under pressure from expectations that a US interest rate increase may come soon.
Spot gold was up 0.1 per cent at $US1,187.70 an ounce, after hitting $US1,183.76 an ounce, the lowest since May 12. US gold futures for June delivery settled down $US1.30 at $US1,185.60.
Gold had dropped 1.7 per cent on Tuesday after firmer US data supported the view that the US Federal Reserve may raise interest rates this year.
"Gold got hit by a double whammy yesterday, first of all from the US dollar move higher, which kicked off on Friday, but also speculative data which showed a 140 per cent jump as of last Tuesday," Saxo Bank's head of commodity research Ole Hansen said.
Positive data on US business investment spending, consumer confidence and house prices on Tuesday was in line with Fed Chair Janet Yellen's comments last week that indicated the US central bank is poised to raise rates later this year.
The euro stabilised in volatile trading and stocks rose after reports that Greece and its creditors had reached an agreement that will provide it with debt relief.
"I think there's still a little bit of risk getting priced into gold, which is why it's showing consolidation," said Eli Tesfaye, senior market strategist for brokerage RJO Futures in Chicago.
"There's not a lot of pressure to sell it and a lot of technical sellers are not going to get aggressive until it starts going below $US1,175."
Tuesday's gold price drop did little to stimulate demand from price-sensitive consumers in Asia, dealers said.
"Following the overnight rout, we were expecting to see some interest from Asia during today's session, however aside from a moderate level of support courtesy of Chinese trade, interest was generally muted," MKS said in a note.
Silver was down 0.3 per cent at $US16.65 an ounce, while platinum was down 0.7 per cent at $US1,115 an ounce.
Silver remains the best-performing precious metal this month despite Tuesday's drop, up 3.2 per cent since the end of April in its biggest monthly rise since January.
Copper hit a one-month low on Wednesday due to concerns about the economic outlook for big metals consumer China, while aluminium fell to its lowest in a year on rising production.
Aluminium is in oversupply with a huge stock overhang, and output has continued to rise this year, with the latest industry figures showing daily average production rising to 68,500 tonnes in April.
Norwegian producer Norsk Hydro said it would increase aluminium output by 35,000 tonnes per year.
"Although LME stocks are falling there's (still) a lot of aluminium around and (then) we see large increases in production. Aluminium needs a deficit to erode overhead stocks," Fastmarkets head of research William Adams said.
London Metal Exchange aluminium hit its lowest since March last year at $US1,731 a tonne, and ended down 0.8 per cent at $US1,738 a tonne.
Copper ended down 0.4 per cent at $US6,080 a tonne, after dropping to its weakest since late April at $US6,075 earlier.
The red metal had been recovering from five and a half year lows hit in January, although the rally has stalled in May.
The euro rose versus the US dollar on reports that Greece and its creditors are closer to striking a deal so the cash-strapped nation would avert default in the coming days. A weaker dollar makes dollar-priced metals cheaper for non-US investors.
Copper got an initial lift on the Greek deal news, only to give back its gains on renewed worries over the lacklustre economic outlook in top metals consumer China.
"Even if you get some early signs which show you some improvement ... the macro story in China doesn't look good," said analyst Dominic Schnider of UBS Wealth Management.
"The only area that is more debatable is the supply side. Here copper gives you a little bit of an edge. We are still calling for a $US6,350 short-term target (three months)."