LONDON: Copper prices slipped to their lowest in more than two weeks on Monday as worries about demand in top consumer China spurred selling, but dwindling inventories outside China offered some support.

Benchmark copper on the London Metal Exchange (LME) was up 0.4% at $9,535 a tonne at 1701 GMT, having earlier touched its lowest since Oct. 13 at $9,418.

"Copper stocks jumped in Shanghai. The overall number isn't high, but it could be the start of a trend, which would suggest weaker Chinese demand," one copper trader said.

INVENTORIES: Stocks of copper in warehouses monitored by the Shanghai Futures Exchange rose more than 20% to 49,237 tonnes last week.

In LME-registered warehouses, copper stocks have nearly halved to 131,300 since late August. Cancelled warrants - metal earmarked for delivery - at 76% suggest LME stocks will fall further over the coming days.

CHINA: Concern about Chinese demand was reinforced by the official manufacturing Purchasing Manager's Index slipping to 49.2 in October, from 49.6 in September.

However, that was partly offset by the Caixin/Markit PMI rising to a four-month high of 50.6 in October as new orders rose and disruptive power shortages eased.

"The big picture is that (China PMIs) remain at odds with sky-high industrial metals prices," Capital Economics said in a note. "Prices have quite a long way to fall over the next year or so as constraints on supply caused by power shortages start to fade."

TECHNICALS: Copper is testing support in the $9,540 and $9,470 area, where the 100-day and 50-day moving averages currently sit. A break below could see the market trying to test $9,300 - the 200-day moving average.

TIN: Shortages and historically low stocks helped tin rise 0.2% to $36,970 a tonne, close to the record high of $38,800 hit in October.

OTHER METALS: Aluminium was little changed at $2,716 a tonne, zinc slipped 0.4% to $3,364, lead ceded 0.1% to $2,381 and nickel was up 1.3% at $19,700.