* Rio Tinto rises on hopes for Chinalco deal
* Reckitt Benckiser up after results
* Banks down; investors fear U.S. plan may come up short * BoE says further easing could include buying gilts
By Dominic Lau
LONDON, Feb 11 (Reuters) - Britain's top share index was flat at midday on Wednesday as oil producers, miner Rio Tinto <RIO.L> and Reckitt Benckiser <RB.L> rose, countering concern the U.S. bank plan may come short of easing a credit crisis.
By 1149 GMT, the FTSE 100 <
> was unchanged at 4,215.32, after trading as low as 4,182.10 to as high as 4,231.17.Rio Tinto surged 6.3 percent to top the FTSE 100 gainers' list, while its shares in Australia <RIO.AX> jumped 6.2 percent on hopes the miner would announce a deal with top shareholder Chinalco to help slash its $39 billion debt burden, when it announces results on Thursday.
Randgold Resources <RRS.L> strengthened 4.1 percent after HSBC upgraded the miner to "overweight" from "neutral".
Reckitt Benckiser <RB.L> rose 4.7 percent after the household cleaning products group met forecasts with a 19 percent rise in 2008 net profits and set cautious 2009 sales and profit targets as the slowdown starts to bite.
Oil producers, however, added the most points to the index as crude prices <CLc1> firmed. BP <BP.L> and Royal Dutch Shell <RDSa.L> put on 0.8 and 0.6 percent, respectively.
Banks, on the other hand, were the main drag on the index on investor concern that the $2 trillion revamped bank rescue plan announced by U.S. Treasury Secretary Timothy Geithner on Tuesday may not be enough to alleviate the credit market turmoil.
Barclays <BARC.L>, Royal Bank of Scotland <RBS.L>, Lloyds Banking Group <LLOY.L> and HSBC <HSBA.L> were off between 0.6 and 2.9 percent.
"The concern for the UK financials is that there was some hope that if the so-called "bad bank" in the U.S. was valued and then implemented, we could see that in the UK. Of course, that remains to be seen," said Richard Hunter, head of UK equities at Hargreaves Lansdown.
A price target cut from Deutsche Bank also weighed on Barclays.
Bank of England Governor Mervyn King said the central bank would probably have to ease monetary policy further and this could include buying gilts to boost the money supply. [
]Sterling fell against the dollar while the short sterling contract rose after a key BoE report showed inflation receding sharply below target, opening the way for further monetary easing.
Unemployment in Britain rose by 146,000 to 1.971 million in the three months to December, the highest level since 1997 but short of analyst forecasts it would breach the two million figure.
Britain's commercial property prices fell 3.5 percent in January continuing their decline after they fell 26.8 percent in 2008, underlining the stiff headwinds buffeting the UK economy.
Land Securities <LAND.L> and Liberty International <LII.L> shed 2.1 percent and 1.5 percent, respectively.
GlaxoSmithKline <GSK.L> also fell after going ex-dividend.
(Editing by Simon Jessop)