BEIJING, Nov 27 (Reuters) - London copper prices extended losses into a third straight session on Tuesday following a report that U.S. President Donald Trump expects to move ahead with raising tariffs on $200 billion of Chinese imports. Copper is down around 15 percent in London so far in 2018 on concerns the U.S.-China trade spat will hurt demand for industrial metals. In an interview with the Wall Street Journal, Trump said it was "highly unlikely" he would accept China's request to hold off on a planned increase in the tariffs from 10 percent to 25 percent due to take effect on Jan. 1. Trump, who is due to meet Chinese President Xi Jinping on the sidelines of the G20 summit in Buenos Aires this week, said that if negotiations were unsuccessful, he would also impose tariffs on the rest of Chinese imports. "Investors continue to monitor the situation around the U.S.-China trade conflict, with the upcoming G20 summit likely to see President Trump and President Xi sit down and discuss a deal," ANZ said in a note. FUNDAMENTALS * COPPER: Three-month copper on the London Metal Exchange had fallen 0.4 percent to $6,164 a tonne by 0522 GMT, extending a 0.3-percent drop from the previous session. The most-traded January copper contract on the Shanghai Futures Exchange slipped 0.3 percent to 49,130 yuan ($7,074.77) a tonne by the end of the morning session. * ZINC: The metal used to galvanise steel fell the furthest in another broad base metals sell-off, slipping as much as 2.2 percent in London to $2,431.50 a tonne, the lowest since Sept. 20. Shanghai zinc was also down 2.2 percent, having hit 19,930 yuan a tonne overnight, the lowest since Sept. 18, as China's ferrous complex continued to lose ground. * COPPER: A hive of mine exploration activity is underway in a remote corner of Western Australia's Great Sandy Desert, led by Rio Tinto Ltd,, which has boosted its holdings 10-fold in the little explored Paterson province in the past year. * SCRAP: China's imports of scrap copper from the United States fell 37 percent from the previous month to just 6,065 tonnes in October, according to Reuters calculations based on customs data released on Monday.