* LME/ShFE arb: http://bit.ly/2wZSAEz
* GRAPHIC-2018 asset returns: http://tmsnrt.rs/2jvdmXl (Recasts, updates prices, adds detail/quote; changes dateline)
LONDON, March 23 (Reuters) - Base metals hit multi-month lows on Friday as the threat of a global trade war that could damage growth escalated after U.S. President Donald Trump announced tariffs on up to $60 billion of Chinese goods.
Trump is planning to impose the tariffs for what he says is misappropriation of U.S. intellectual property, but only after a 30-day consultation period that starts once a list is published.
Still, the escalating tensions have sent jitters through financial markets as investors see dire consequences if the world's two largest economies, the United States and China, start erecting trade barriers.
In London, copper, aluminium and zinc hit their weakest since mid-December, while in Shanghai, copper retreated towards levels not seen since mid-2017, although prices cut their losses towards the end of the Asian day.
"We expect copper to continue to rise during the course of the year reflecting the supply deficit but obviously we're watching what could develop into a trade war, if it does, it changes everything," said Nitesh Shah, commodity strategist at ETF Securities.
* COPPER: London Metal Exchange copper was down 0.6 percent at $6,655 a tonne at 1127 GMT, having plumbed its weakest since mid-December at $6,623.50. Prices extended falls from the previous session, breaking the 200-day moving average for the first time in around 18 months.
* CHINA: China's commerce ministry said the country was planning measures against up to $3 billion of U.S. imports to balance U.S. tariffs against Chinese steel and aluminium.
* NICKEL, ZINC: A sell-off in steel spilled into inputs nickel and zinc. Shanghai rebar tumbled near 7 percent, while LME nickel slid 1.2 percent to $13,030, having earlier hit its lowest since mid-February. Zinc fell 0.1 percent to $3,200, having earlier hit its lowest since mid-December.
* ALUMINIUM: LME aluminium fell 0.4 percent to $2,066, having earlier hit three-month lows after breaking below the 200-day moving average earlier this month.
* STEEL: Chinese steel traders fear a prolonged market downturn as prices skid to their lowest in years.
* NICKEL DEFICIT: The global nickel market deficit widened to 15,800 tonnes in January, industry data showed.
* SHANGHAI ALUMINIUM: Aluminium inventories in warehouses monitored by the Shanghai Futures Exchange rose on the week to a record high of 940,318 tonnes.
* SCRAP: China's scrap metal imports fell by 38.5 percent year on the year as the country enforced its clampdown on foreign waste.
(Additional reporting by Melanie Burton, editing by David Evans)