(Recasts, adds Shanghai closing prices, updates London prices) MELBOURNE/BEIJING, March 7 (Reuters) - London metals slipped on Wednesday on the resignation of Gary Cohn, a key advocate for free trade in the White House, rekindling fears U.S. President Donald Trump would go ahead with tariffs on metal imports and risk a trade war. Cohn, an economic adviser seen as a bulwark against protectionist forces within Trump's administration, said on Tuesday he would resign, a move that came after he lost a fight over Trump's plans for hefty steel and aluminium import tariffs. The threat of a trade war has led to speculative buying, Kingdom Futures CEO Malcolm Freeman wrote in a note, on expectations that metal will be harder and more expensive to come by when the tariffs are imposed. However, there has so far been little increase in real consumer buying, he added. "The net result of this could well be another sharp correction to the downside in prices until the markets get into synchronisation and consumer buying starts up again," Freeman said. FUNDAMENTALS * LME COPPER: London Metal Exchange copper was down 0.5 percent at $6,970 a tonne, as of 0730 GMT, shedding gains of 1.4 percent from the previous session. Prices have traded in a $6,850-$7,250 range since mid-February. "A softer dollar brought copper up above $7,000 last night, but I think fear is on again," said a trader in Singapore. * LME OPTIONS: Traders of LME calls and puts, the right to buy or sell a contract at a fixed price later, must decide today, the first Wednesday of the month, whether to exercise their options. * SHFE COPPER: Shanghai Futures Exchange copper closed 0.3 percent higher at 52,480 yuan ($8,299.33) a tonne. * DOLLAR: The greenback extended its retreat on Wednesday after Cohn resigned. * CHINA ECONOMY: China is fully confident of its ability to fend off systemic debt risks while authorities expect no significant changes in government debt ratio in the coming years, finance minister Xiao Jie said on Wednesday. * ZINC: Brazilian miner Nexa Resources expects demand for zinc to outpace supply, keeping prices for the metal at $3,400 to $3,500 a ton for the rest of the year, Chief Executive Tito Martins said on Tuesday. * ZINC: Premiums for zinc in Shanghai bond have sunk to the weakest since May last year at $145-170, latest data shows, after exchange stocks in the U.S. surged this week, soothing supply concerns. ZN-BMPBW-SHMET * For the top stories in metals and other news, click or MARKETS NEWS * Global stocks and the dollar slumped on Wednesday after a strong White House advocate for free trade resigned, fanning fears that President Donald Trump will proceed with protectionist tariffs and risk a trade war. PRICES BASE METALS PRICES 0717 GMT Three month LME copper 6973 Most active ShFE copper 52480 Three month LME aluminium 2138 Most active ShFE aluminium 14260 Three month LME zinc 3297 Most active ShFE zinc 25300 Three month LME lead 2422 Most active ShFE lead 18710 Three month LME nickel 13505 Most active ShFE nickel 102070 Three month LME tin 21380 Most active ShFE tin 146560 BASE METALS ARBITRAGE LME/SHFE COPPER LMESHFCUc3 1098.33 LME/SHFE ALUMINIUM LMESHFALc3 -1448.78 LME/SHFE ZINC LMESHFZNc3 604.98 LME/SHFE LEAD LMESHFPBc3 124.99 LME/SHFE NICKEL LMESHFNIc3 1453.89 ($1 = 6.3234 Chinese yuan) (Reporting by Melanie Burton and Tom Daly in BEIJING; Editing by Amrutha Gayathri and Sherry Jacob-Phillips)