* Comex copper specs trim net long position in latest week - CFTC
* Coming Up: U.S. Federal budget April at 1800 GMT (Updates prices)
By Melanie Burton
SYDNEY, May 12 London nickel jumped by nearly 5 percent on Monday, extending a winning streak that has fuelled gains of more than 12 percent in May alone as investors and consumers stock up on prospects of a worsening supply shortfall later in the year.
London copper hit the highest in two months, fuelled by steady buying and short-covering which also helped Shanghai copper rally by 2 percent.
Nickel prices have rocketed by nearly 50 percent since January due to a ban on ore shipments from top exporter Indonesia that has triggered hoarding, while speculation that sanctions against Russia may hit top nickel producer Norilsk Nickel have poured fuel on the bullish sentiment.
"It's on the back of the Ukraine and continuing supply constraints from Indonesia," said James Glenn, analyst at National Australia Bank in Melbourne.
"If there is a large (speculative) factor at play...you might see some of that start to unwind with the Chinese industrial production data if it disappoints on Tuesday," he added.
LME nickel struck $20,870 a tonne, its loftiest since Feb. 2012 before trading at $20,650 a tonne at 0701 GMT, still a gain of 3.7 percent.
Nickel buyers in China and Japan are scrambling to secure supplies as roaring prices and a fear of shortages boost demand for both refined metal and long-term ore contracts from stainless steel makers.
The price of nickel ore from the Philippines has more than doubled since late February, as supplies have dried up from rival producer Indonesia, previously the world's biggest exporter.
Prices for nickel on China's mainland are continuing to run ahead of even LME prices, one trader said.
Traders are watching for an announcement later in the session on new Russian companies and people to be sanctioned over Ukraine.
A shutdown of Vale's New Caledonian nickel operations after an effluent spill late last week is expected to be short-lived, but it still fanned sentiment.
Elsewhere, LME copper prices attracted larger than usual volumes of buying in the Asian time zone, with traders noting short availability of supply in top consumer China.
Three-month copper on the London Metal Exchange climbed 1.3 percent to $6,830 a tonne, its highest since March 7.
The most-traded August copper contract on the Shanghai Futures Exchange rallied 2 percent to 48,020 yuan ($7,700) a tonne, also a two-month high before settling at 48,010.
Hedge funds and money managers cut their net bullish position copper futures and options in the week to May 6, according to data from the Commodity Futures Trading Commission on Friday.
Fanning bullish sentiment in Chinese stocks, which traders said may have spilled into metals, China pledged on Friday to push ahead with a broad range of capital market reforms as it seeks to encourage more efficient capital allocation, increase foreign investment and improve transparency of its markets.
In other news, the U.S. economy should accelerate in the second quarter to an annual growth rate of 3 percent or more, but it may not be clear for some time if the pick-up is sustainable, a Federal Reserve official said.
Three month LME copper
Most active ShFE copper
Three month LME aluminium
Most active ShFE aluminium
Three month LME zinc
Most active ShFE zinc
Three month LME lead
Most active ShFE lead
Three month LME nickel
Three month LME tin ($1 = 6.2280 Chinese Yuan) (Editing by Richard Pullin and Muralikumar Anantharaman)