Base metals have closed little changed on the London Metal Exchange LME as investors weighed weak economic indicators against the hope of further stimulus by central banks.

At the PM kerb close on Monday, LME three-month copper was 0.1 per cent lower at $US7,690 a metric ton. Aluminum closed up 0.4 per cent at $US1,917.5/ton.

Concerns over slowing global growth damped market sentiment after China's premier warned that the country's economic recovery is not yet stable and US retail sales fell unexpectedly fell in June.

US retail sales fell for the third straight month in June, the Commerce Department reported, bucking economists' projections for a slight increase and marking the first three-month streak of declines since 2008.

Manufacturing activity in New York, meanwhile, rose more than expected in July, though new orders in the region sunk into territory indicating contraction for the first time since November, according to the Federal Reserve Bank's Empire State Manufacturing Survey.

"Risk assets headed lower on a combination of anxieties surrounding global economic expansion (the inverse thereof to be specific), and persistent systemic troubles in the euro zone and China," said Kitco Metals analyst Jon Nadler.

Early base metal losses were pared later in the session, however, as the euro strengthened versus the US dollar and hopes for further economic stimulus provided some underlying support to prices, said a London-based broker.

"Markets are still waiting for stimulus," said the broker.

"They won't move much lower in case they are caught out by [changes in] monetary policy," he added.

In this regard, market participants are likely to closely watch Federal Reserve Chairman Ben Bernanke's testimony to Congress on Tuesday and Wednesday for signs that a third round of quantitative easing might be on the cards.

Any indications of further monetary easing will likely push prices higher, while any lack of stimulus signals would likely spur selling on the LME.

Prices in dollar a metric ton.

3 Months Metal Bid-Ask Change from

Friday PM kerb

Copper 7,690.0-7,691.0 Dn 10

Lead 1,899.5-1,900.0 Up 20.5

Zinc 1,889.0-1,890.0 Up 15

Aluminum 1,917.5-1,918.0 Up 8

Nickel 16,200.0-16,225.0 Up 50

Tin 18,750.0-18,775.0 Dn 30

Aluminum Alloy 1,815.0-1,820.0 Up 5

Aluminum Alloy-NASAAC 1,910.0-1,925.0 Up 5