Reduced trade was discouraging investors and merchants from placing new import orders for spot copper, which could trim arrivals in the world's top copper consumer next month, traders said. Premiums, paid by buyers to sellers in addition to cash London Metal Exchange copper prices, have fallen about 10 percent from last week despite a fall in the supply of copper stocks in bonded warehouses in Shanghai, China's most popular destination for refined copper imports. "We cannot sell at good premiums. But even at lower premiums, there have been very few deals done so far this week," said a trader at a large Chinese trading firm. The firm had resold bonded copper at premiums of about $135 this week versus $150 last week, he added. Chinese buyers were unwilling to trade because a crucial euro zone summit later this week may move international prices, he said. The $135 premium is still higher than the $120-$130 at which material changed hands in mid-November and $110 offered by the world's top copper producer, Chile's Codelco for shipments in 2012. Traders said offers for bonded copper stayed at premiums of about $140-$150 per tonne over cash LME prices versus $150-$180 last week. "The arbitrage was not bad last week and investors were buying. But that has changed this week," said a trader at an international trading house, which holds bonded stocks in Shanghai. He was referring to gaps between cash LME copper prices and Shanghai prices. BONDED STOCKS Bonded stocks, in Shanghai but not yet assessed for China's 17 percent value-added tax, are the most popular type among Chinese importers, since they offer the shortest delivery time. The stocks were estimated at about 260,000-270,000 tonnes, compared to about 300,000-330,000 tonnes in the middle of last month. Bonded copper had fallen after investors and merchants paid the VAT and resold the metal in the domestic market in the previous 2-3 weeks, traders said. Traders said the process of obtaining VAT payment receipts from customs offices in Shanghai slowed this month because local offices were wrapping up for the year-end, delaying deliveries of bonded stocks to buyers, who will need the receipts when reselling the metal in the domestic market. Traders said the slowdown had happened in earlier years and this year was slower than others. In the domestic market, fabricators who use refined copper to make semi-finished and finished products such as rods and power cables had cut buying of spot copper because they need cash to settle debts with other firms and yearly loans with banks before the end of the year, cutting the cash available for copper purchases, traders said. "Supplies of imported copper are abundant," a trader at a large copper smelter said. "But it's hard to sell spot metal since fabricators need to pay back their loans and debt. They are also not keen to take new orders because they don't want to add payables.”