By Sara Sjolin, MarketWatch
LONDON (MarketWatch) -- Mining firms led U.K. stocks lower on Thursday, with sector heavyweight BHP Billiton PLC leading the retreat after a broker downgrade, while business-activity data from the euro zone weighed on broader sentiment.
The FTSE 100 index lost 1.6% to close at 6,291.54, marking the worst daily performance since July last year.
Shares of BHP Billiton (>> BHP Billiton Limited) lost 4%, after Citigroup cut the miner to neutral from buy, saying that positive catalysts such as capital-expenditure cuts and cost reductions are now priced in.
Other mining firms were also on the decline, as most metals prices turned lower. Shares of Rio Tinto PLC (>> Rio Tinto plc) shaved off 3.5%, Vedanta Resources PLC fell 4.1% and Anglo American PLC gave up 1.4%. .
Oil prices dropped, adding pressure on U.K. oil firms. Shares of BG Group PLC erased 0.7%, Royal Dutch Shell PLC (RDSB) fell 1.3% and BP PLC (>> BP plc)eased 1.1%. .
For the broader stock market, investors reacted to lackluster macroeconomic data from the euro zone. The preliminary composite purchasing-managers' index for the region slumped to a two-month low of 47.3 in February from a January reading of 48.6, coming in below analysts' expectations. .
The pan-European Stoxx Europe 600 index gave up 1.5% 284.86. .
Banks were among major decliners in London. Lloyds Banking Group PLC dropped 3.1%, Barclays PLC (>> Barclays PLC) fell 4.2% and Royal Bank of Scotland Group PLC (>> Royal Bank of Scotland Group plc) lost 2.2%. Heavyweight HSBC Holdings PLC (>> HSBC Holdings plc) eased 2.3%.
On a more upbeat note in London, shares of BAE Systems PLC jumped 4.1%, after the aerospace and defense firm said it sees modest earnings-per-share growth in 2013 and launched a three-year one billion pound ($1.5 billion) shares buyback program. and .
Shares of Rexam PLC rose 0.7% to GBP5.05 ($7.67) a share, as Citigroup reiterated its buy rating on the packaging company and lifted the price target to GBP5.70 from GBP5.12.
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