* Chinese speed up plans to build Indonesian refineries
* World Bank raises forecast for global growth
* Japan's PPC, BHP fail to reach 2014 copper TC/RC term deal
(Updates prices, adds comment)
LONDON, Jan 15 (Reuters) - Nickel prices hit two-month highs on Wednesday due to supply concerns following an Indonesian ban on unprocessed ore exports, but gains are likely to be capped by persistent weakness in the stainless steel market and ample ore stockpiles in China.
Nickel, a key component of stainless steel, has surged more than 8 percent since Thursday on the back of the Indonesian ban, which came into force at the weekend.
Analysts said that while there has been an immediate reaction following the ban, prices are likely to remain capped by a weak stainless steel market, a surplus of nickel this year and adequate stockpiles of nickel ore in China.
Three-month nickel on the London Metal Exchange fell to a session low at $14,224 a tonne before recovering to a high of $14,622, up from $14,340 at Tuesday's close and its highest level since early November.
"Although nickel has firmed by about $1,000 (a tonne) in the last two weeks, prices have certainly not run away, with values still below their Q4 2013 highs," said Ed Meir, an analyst at INTL FCStone.
"There is ongoing softness in the stainless market, while on the raw material side, the Chinese have been stockpiling nickel ores for months now and are not necessarily scrambling to cover their needs."
Industry sources said Chinese firms were speeding up plans to build refineries in Indonesia to produce nickel pig iron, a substitute for higher grade refined nickel in stainless steel, following the move by Jakarta to force miners to build local processing plants.
"Yes, there is an impact, but probably not so much this year because China has got stockpiles of ore. It imported huge amounts from Indonesia last year," said Robin Bhar, an analyst at Societe Generale.
COPPER DEMAND EASES
Copper edged up, supported by economic optimism after the World Bank raised its forecast for global growth, but gains were capped as demand eased ahead of the Chinese Lunar New Year.
Copper prices have been stuck in a rut so far in 2014, capped by expectations that supply will climb as the year gets underway but underpinned by a shortfall of available metal in physical markets.
LME copper was at $7,344 a tonne at 1600 GMT, up from a last bid of $7,280.
"Definitely there is less demand for copper at the moment. Because of seasonal reasons, demand for all commodities is going to weaken, which will be the case until early February," analyst Wan Ling at metals consultancy CRU in Beijing said.
China is the world's top copper consumer, accounting for around 40 percent of global refined demand. Its Lunar New Year holidays kick off on Jan. 31.
In industry news, Pan Pacific Copper, Japan's biggest smelter, said on Wednesday it would not sign a long-term contract for copper processing fees with global miner BHP Billiton in 2014, after the two sides could not agree on terms.
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 = 6.0412 Chinese yuan)
(Additional reporting by Melanie Burton; editing by Jane Baird and Anthony Barker)