* Sluggish demand in China, more stimulus unlikely now
* All other base metals hit lowest in more than a month
* Large build up in LME lead stocks
* Coming Up: U.S. Fed begins two-day meeting
(Adds closing prices) LONDON, Oct 23 (Reuters) - Copper slid to a six-week low on Tuesday, giving up more gains from its September rally, as a strong dollar, renewed worries over Spain's sovereign debt and a lack of robust demand from China knocked investor risk appetite. Also weighing was a fall in U.S. stock markets, which were hurt by disappointing quarterly results and outlooks from a host of large multinational companies. Stocks markets are seen by some as a proxy for economic growth. In Europe meanwhile, Spanish borrowing costs rose after Moody's cut the credit ratings of five of the country's indebted regions, while business morale in France's manufacturing sector slumped to its lowest level in more than two years. Three-month copper on the London Metal Exchange ended at $7,831 a tonne, down from $7,953 at the close on Monday. Earlier it dropped to an intraday low of $7,807.75, its weakest point since Sept. 7. Aluminium, lead, zinc, tin and nickel also hit their lowest in more than a month. ``Exogenous factors are still in control and the market is still waiting for some direction from China or elsewhere,'' said analyst Leon Westgate at Standard Bank in London. ``But I'm not sure there's any reason for China to be very enthusiastic about switching the (stimulus) taps back on. I would expect more concrete plans to emerge next year, rather than this year, particularly as the data hasn't been that bad.'' Speculators who track momentum levels were now going short in copper after the market violated key support levels and slipped below the 50-day and 200-day moving averages, traders said. Copper powered higher in September, driven by announcements of central bank stimulus measures, but has given up a large portion of that rally. ``LME copper prices have continued to drop and have now retraced almost 50 percent of their $1,100 rally. Although this does not rule out the possibility of a further upside move, it does reduce the likelihood of that scenario significantly,'' broker Marex Spectron said in a note. The cancellation of 11,550 tonnes of copper in LME warehouses in New Orleans may offer some support. It could create more bottlenecks and tighten the short-term availability of material, causing speculators to be more cautious in shorting the market, Westgate said. Investors were cautious ahead of the Fed's two-day meeting starting on Tuesday, though the central bank is likely to hold off from fresh steps, opting to review the impact of action it took last month. Further weighing on the market was a stronger dollar against the euro, which makes dollar-priced commodities more expensive to Europeans, and losses on equities markets. The single currency was hurt by the Moody's downgrades, and rising Spanish, Portugese and Italian bond yields. In China's physical markets, traders said copper prices were supported by some seasonal buying, although volumes were light in comparison with the same period in previous years. ``October is usually the start of the fourth quarter peak-season buying in copper, but we still haven't seen a lot of restocking so far. Most people believe sales volumes will pick up soon, but the question is how much can they pick up this year?'' a Shanghai-based trader said.
LEAD STOCKS RISE LME three-month lead ended at $2,023 a tonne from Monday's close of $2,070, having hit its lowest since early September at $2,012.25 earlier. LME lead inventories rose by 12,375 tonnes to 312,550 tonnes due to arrivals at Antwerp warehouses. LME lead stocks had been falling steadily during most of the year, but since Oct. 8 they have rebounded by 26 percent. Aluminium closed at $1,947 a tonne from $1,960, having hit its lowest since early September at $1,929 a tonne. Barclays reiterated its gloomy call on the market due to an extended outlook for oversupply following discussions during LME Week. ``Our bearish view on aluminium was further reinforced following our meetings with producers which revealed no plans to cut production, despite surplus generation and low prices,'' analyst Gayle Berry said in a note released on Monday evening. ``Chinese production growth is expected to accelerate into 2013 short of an unlikely pull back in subsidy support, which will keep the domestic market over supplied and support growth of semis exports.'' Zinc ended at $1,847 a tonne from a close of $1,856 on Monday, having hit its lowest since late August at $1,830 a tonne. Tin closed at $20,255 a tonne from $20,450, having hit its lowest since mid-September at $20,125 and nickel ended at $16,355 a tonne from Monday's close of $16,590, having hit $16,139 earlier, its lowest since early September. Metal Prices at 1621 GMT Comex copper in cents/lb, LME prices in $/T and SHFE prices in yuan/T