* FTSE 100 falls 0.7 percent, commods pressured by China worries
* Engineers weak as Invensys update disappoints
LONDON, Jan 20 (Reuters) - Weaker commodity stocks dragged Britain's top share index lower on Thursday, after data from China heightened the potential for further monetary tightening by the world's most voracious consumer of raw materials.
By 1151 GMT, the FTSE 100 was down 86.08 points, or 1.4 percent, at 5,890.62. London's blue chips now trade flat in 2011, having ebbed away from a 31-month high of 6,090.49
The index has lost 2.7 percent so far in the past two trading sessions, haunted by worries over an overheating Chinese economy and swirling euro zone debt concerns, which has forced investors to batten down the hatches.
"The market is not as comfortable as it was 48 hours ago. Sentiment is driven by what is happening away from UK PLC; worries about growth worldwide and concerns about inflationary pressure is blighting the market," Martin Dobson, head of trading at Westhouse Securities, said.
Miners and energy stocks were weaker, tracking lower commodity prices, after data showed China ended 2010 with a bang.
China's growth soared past forecasts and inflation slowed less than expected, numbers that could prod the government to intensify its easy-does-it approach to tightening.
China concerns took the gloss off BHP Billiton's 4 percent rise in quarterly output.
The iron ore miner, which fell 2.2 percent, also said Australia's devastating floods will hit production and sales at its coal mining operations for at least six more months.
Traders said Burberry, off 4.2 percent, was being hurt by the luxury goods group exposure to China.
ENGINEERS DERAILED
Engineering group Invensys was the worst performing blue chip stock, down 7 percent, as weakness in orders at its rail division soured an in-line trading update.
Fellow engineer Weir Group fell 4.3 percent with traders citing a slight read-across from Invensys and recent downbeat comment from brokers, which doused the flames of a potential deal with Swiss peer Sulzer.
On the macroeconomic front British factory orders unexpectedly fell in January.
A warning about weather damage to the UK sugar beet crop cost food producer to clothing retailer AB Foods 3.2 percent.
HSBC slipped 1 percent among otherwise firmer banks ahead of Morgan Stanley's fourth-quarter results due at 1230 GMT.
U.S. stock index futures pointed to a flat open on Wall Street after Wednesday's sell off and ahead data including home sales for December, weekly jobless claims and the Philadelphia Fed business index for January.
On the upside, National Grid added 1 percent, as JP Morgan raised its rating to "overweight" from "neutral" on valuation grounds.
Scottish & Southern Energy climbed 1 percent with other blue-chip utilities which found support as their defensive attractions came into play, and after a positive note on the sector from Investec. (Editing by Hans Peters)