By Dominic Lau
LONDON, April 30 (Reuters) - Britain's top share index fell 0.7 percent by midday on Wednesday ahead of an expected interest rate cut in the United States, as commodity shares tracked weaker raw material prices and HBOS <HBOS.L> led banks lower.
By 1038 GMT, the FTSE 100 <
> was down 44.8 points at 6,044.6. The UK's benchmark index has gained 6 percent so far this month, on track for its best monthly percentage rise in five years.Miners fell in line with metal prices and after Kazakhmys <KAZ.L> posted an 18.4 percent fall in first-quarter copper cathode production due to smelter shutdown. It said output should recover in the second half after a "subdued" second quarter. Kazakhmys was 4.7 percent lower.
Vedanta Resources <VED.L>, Lonmin <LMI.L>, Rio Tinto <RIO.L>, BHP Billiton <BLT.L> and Anglo American <AAL.L> were down between 0.3 and 6.1 percent.
Oil majors BP <BP.L> and Royal Dutch Shell <RDSa.L> dipped after a shar rise in the previous session's sharp due to their forecast-beating results, and as crude prices <CLc1> eased.
Gas producer BG Group <BG.L> shed 4.8 percent after it said it planned a $12 billion bid for an Australian utility. BG beat forecasts with a 78 percent jump in first-quarter profit, powered by high gas and oil prices and rising production. All eyes are on the U.S. Federal Reserve's rate decision, due after European market closes. The Fed is expected to cut rates by a modest quarter percentage point and may suggest the rate-cutting cycle it kicked off last autumn has reached an end.
"Because of all the speculation that the Fed may cut by a quarter of percentage point this evening and then go on an extended summer holiday ... the market may take that as an indication that the dollar might actually recover some of its poise," said Jeremy Batstone-Carr, head of private client research at Charles Stanley.
"To the extent, the speculative enthusiasm for things like raw materials that have been built up as a consequence to the correlation of the dollar might unwind a little bit."
But Batstone-Carr said he expected the dollar to remain weak because of "structural concerns" in the U.S. economy.
U.S. gross domestic data are also due later in the day.
GLOOMY OUTLOOK WEIGHS ON HBOS
Banks were also down after analysts cut their earnings forecasts and price targets for HBOS <HBOS.L>, which announced a 4 billion pound rights issue on Tuesday.
HBOS lost 4.2 percent, while both Barclays <BARC.L> and Royal Bank of Scotland <RBS.L> dropped 2.9 percent and Lloyds TSB <LLOY.L> slipped 2.6 percent.
HSBC <HSBA.L>, however, was up 0.9 percent after Goldman Sachs upgraded the bank <0005.HK> to "buy" from "sell".
Home Retail Group <HOME.L> advanced 5.7 percent to top the gainers' list on the FTSE 100 after it reported a 15 percent rise in annual profits even though it said the outlook for consumer spending was weaker for the new fiinancial year.
Admiral Group <ADML.L> was up 4.5 percent after Citigroup upgraded its rating on the car insurer to "buy" from "hold".
Pay TV-firm BSkyB <BSY.L> put on 2.5 percent after it added 56,000 net new customers in the third quarter, in line with forecasts, and said it was on track for the full year.
GlaxoSmithKline <GSK.L>, G4S <GFS.L>, Reed Elsevier <REL.L> and Wm Morrison Supermarkets <MRW.L> all fell after going ex-dividend.
AstraZenca <AZN.L> added 1.2 percent. The Anglo-Swedish drug maker was seeking U.S. approval to sell its asthma drug Symbicort for chronic obstructive pulmonary disease, ramping up competition with GlaxoSmithKline's Advair. (Additional reporting by Michael Taylor) (Editing by Richard Hubbard) (dominic.lau@reuters.com; +44 20 7542 5440; Reuters Messaging: dominic.lau.reuters.com@reuters.net))