The price of copper tumbled Wednesday to the lowest level for more than five years after the World Bank slashed its global economic forecasts.

Copper for delivery in three months plunged in Asian trading hours to $5,353.25 per tonne, a level last seen in July 2009. That marked an 8.0-percent slide from Tuesday's close.

Japan approved its largest-ever defense budget for the next fiscal year on Wednesday, as hawkish Prime Minister Shinzo Abe looks to strengthen surveillance of territorial waters in the face of a continuing spat with China.

For the year to March 2016, Tokyo will spend 4.98 trillion yen ($41.97 billion), the government said, indicating a budget rise for the third straight year.

Inflation in Russia could hit 17 percent this year, the deputy economy minister said Wednesday, as the ruble suffers on the back of slumping oil prices.

"Peak inflation will come in March-April when year-on-year inflation could reach 15 to 17 percent," Alexei Vedev was quoted as saying by the state-run TASS news agency.

Chinese e-commerce giant Alibaba will take a majority stake in AdChina, which calls itself China's leading digital marketing platform, to develop online and mobile marketing, the Internet powerhouse said Wednesday.

Alibaba had made a strategic investment in AdChina, it said in a statement, without giving the amount. An Alibaba spokeswoman said financial details were not disclosed.

Oil prices on Tuesday slipped further toward six-year lows in Asia after major crude producers stressed they will maintain output levels despite an oversupply.

U.S. benchmark West Texas Intermediate (WTI) for February delivery was down 58 cents at $45.31 a barrel in afternoon trade and Brent crude for February dropped 54 cents to $46.05.

Kuwait said Tuesday that the sharp fall in world oil prices is unjustified but that the market may not improve before the second half of this year.

"Nobody can justify the drop now," Oil Minister Ali al-Omair told reporters as prices slid towards six-year lows.

President Hassan Rouhani said Tuesday that Iran would withstand the economic pain of falling oil prices, suggesting Saudi Arabia would suffer more in the long run from the current slump.

Iran has been among the oil exporting countries worst hit by a more than 50 percent slide in the price of crude in recent months, given its budget was based on sales at $100 per barrel.

The Russian ruble tumbled against the dollar and the euro for the second day in a row on Tuesday, punished as oil prices plunged further.

The ruble was worth 64.68 against the dollar and 76.43 against the euro at around 0900 GMT, down from 63.17 and 74.68 on Monday evening.

The German government managed to balance its books for the first time since 1969 in 2014 and a year ahead of target, the finance ministry said Tuesday.

Originally, the government had been penciling in a small budget deficit of 6.5 billion euros ($7.7 billion) for 2014.

The United Arab Emirates said on Tuesday that OPEC will no longer move to shore up crude prices, arguing that rising North American shale oil output needs to be curbed.

World prices have been falling since June but the pace of the slide accelerated in November when the Organisation of the Petroleum Exporting Countries (OPEC) decided to maintain its production unchanged at 30 million barrels per day.