* Weak oils weigh
* Banks, miners rally
* Results lift Reed Elsevier, BAE; dent Rexam, Kingfisher
By Jon Hopkins
LONDON, Feb 19 (Reuters) - Britain's top share index fell 0.4 percent by midday on Thursday, retreating from early gains as a rally by banks and miners was offset by weakness in heavyweight oils and investors mulled a mixed bag of results.
By 1152 GMT, the FTSE 100 <
> was down 15.28 points at 3,991.55, back below the 4,000 level, having fallen 0.7 percent in the previous session."FTSE is trading in such a tight range around the 4,000 level, everyone is waiting for a break-out in one particular direction, but it hasn't done that yet today," said Ben Timms, senior derivatives trader at CFD specialists Blue Index.
"Whether that will come with the U.S. jobless claims and PPI numbers this afternoon is still to be seen," Timms said. "But until then we are just patiently waiting."
Weakness in oil majors was the main drag on blue chip sentiment, as crude prices <CLc1> stayed around the $35 a barrel level. BG Group <BG.L> was down 1.7 percent and BP <BP.L> was off 1.1 percent, while Royal Dutch Shell <RDSa.L> lost 0.5 percent.
Miners were mostly higher as metal prices firmed slightly, reflecting a dip in the dollar.
Kazakhmys <KAZ.L>, Eurasian Natural Resources <ENRC.L>, Vedanta Resources <VED.L> and Rio Tinto <RIO.L> gained between 0.3 percent and 4.5 percent.
The Times reported that leading shareholders in Rio Tinto want Jim Leng to be reinstated as its chairman designate in a move that threatens to throw the board of the embattled miner into turmoil.
Xstrata <XTA.L> fell 0.4 percent after a Guardian report that it is facing a potential revolt from shareholders over its 4 billion pound fundraising as big City investors prepare to counter government claims they are ineffectual in exercising influence.
Another rally by hard-pressed banks was one of the main positives for UK blue chips. Royal Bank of Scotland <RBS.L>, Lloyds Banking Group <LLOY.L>, and Barclays <BARC.L> made up the top three FTSE risers, ahead 6.7 percent to 9.4 percent.
Stock futures <DJc1> pointed to an early rise on Wall Street on Thursday, with UK blue chips having eked out a modest gain Wednesday as investors assessed U.S. President Barack Obama's pledge of up to $275 billion to help families refinance their mortgages.
RESULTS REACTION MIXED
Professional publisher Reed Elsevier <REL.L> was among the top blue-chip gainers, up 2.3 percent after it reported a 24 percent rise in 2008 adjusted earnings per share, as its low exposure to advertising shielded it from the downturn.
BAE Systems <BAES.L> added 2.7 percent after Europe's biggest military contractor said it expected good growth in 2009 after earnings for the previous year came in slightly ahead of forecasts.
Kingfisher <KGF.L> fell 2.7 percent after Europe's biggest home improvements retailer posted a 5.5 percent fall in fourth-quarter underlying sales but said it was on track to meet analysts' full-year profit forecasts.
Rexam <REX.L> topped the FTSE 100 fallers list, down 8.9 percent, as the beverage-can maker highlighted in its in-line full-year results that it faced worsening market conditions.
Property issues were also under pressure from ongoing fund raising moves.
Land Securities <LAND.L> lost 3 percent after Britain's largest real estate company, joined the scramble for capital among debt-starved property investors with a 756 million pounds rights issue.
Liberty International <LII.L> shed 0.9 percent after the firm said it was also weighing up capital raising options. (Editing by Karen Foster)