* LME/ShFE arb: http://tmsnrt.rs/2oQ5nm2 (Updates with official prices)
LONDON, July 26 (Reuters) - Copper prices rose for a fourth day on Wednesday to the highest in more than two years on expectations of strong economic growth in China and news of Chinese restrictions on scrap imports that would increase demand for imported refined copper.
A weaker dollar and forecasts of tight supplies supported price gains, said ABN AMRO analyst Casper Burgering, with aluminum, nickel and zinc also at, or near, multi-month highs.
But traders said gains faltered once European markets opened as investors cashed in on higher prices.
COPPER: Benchmark copper on the London Metal Exchange traded up 0.7 percent in official rings at $6,270 a tonne after earlier touching $6,400, its highest since May 2015. Copper has climbed more than 5 percent since July 20 as rises above key technical levels triggered further buying.
STOCKS: On-warrant stocks available to the market at LME-registered warehouses fell to 221,125 tonnes after 6,425 tonnes of cancellations, but were still up from a low of around 140,000 tonnes in May. <MCUSTX-TOTAL>
CHINA SCRAP BAN: Traders said prices rose on news that China could ban imports of some scrap metal, including copper, from the end of 2018. This would increase demand for imported refined copper.
BAN IMPACT: However, metals researcher Antaike said that the ban would likely affect less than 1 million tonnes of imports that market participants were speculating could be impacted.
CHINA GROWTH: Metals were also supported by a better demand outlook from China after second-quarter growth beat expectations and the International Monetary Fund raised the country's 2017 growth forecast.
DEMAND: China accounts for nearly half of global copper consumption estimated at 23 million tonnes this year.
CHINA MARKETS: China's securities regulator pledged on Wednesday to expand access to capital markets for all types of investors.
U.S. FED: The Federal Reserve is expected to hold interest rates unchanged in a decision to be announced at 1800 GMT.
CURRENCY: The U.S. dollar has weakened for five consecutive months, making dollar-priced metals cheaper for holders of other currencies.
FREEPORT: Key issues still need to be resolved before U.S. miner Freeport McMoRan Inc gets a new operating permit for its huge Grasberg copper mine, the world's second largest, a mining ministry official said.
ANTOFAGASTA: Chile's Antofagasta said copper production in the first half rose 7.1 percent and kept its full-year cost and output guidance.
PRICES: Aluminium traded up 0.2 percent at $1,933 a tonne in official rings. Nickel traded 0.6 percent lower at $9,955 a tonne, zinc did not trade but was bid down 1 percent at $2,809, lead traded down 0.4 percent at $2,308 and tin was bid 0.1 percent higher at $20,325 a tonne.
(Additional reporting by Melanie Burton; Editing by Edmund Blair and Louise Heavens)