* FTSE 100 closes down 0.2 pct at 4,163.61
* Investors digest 100-bps interest-rate cut
* Oils, banks rise; miners fall
By Rebekah Curtis
LONDON, Dec 4 (Reuters) - Britain's FTSE 100 <
> ended a volatile session slightly lower on Thursday as investors digested a 100-basis point cut in interest rates and losses in miners eclipsed stronger oils.Britain's benchmark share index closed down 6.35 points, or 0.2 percent, at 4,163.61 points, having whipsawed in a trading range of 4,090 and 4,261 points.
The Bank of England slashed borrowing costs by a full percentage point to shore up Britain's deteriorating economy and stave off the threat of deflation.
The central bank warned further measures would be required to hold the economy back from plunging into deep recession.
The European Central Bank cut interest rates a record 75 basis points to 2.50 percent and forecast the euro zone would stay in recession next year.
Among banks, HBOS <HBOS.L> added 7.4 percent, HSBC <HSBA.L> gained 1.7 percent and Royal Bank of Scotland <RBS.L> also rose. But Lloyds TSB <LLOY.L>, Barclays <BARC.L> and Standard Chartered <STAN.L> all closed lower.
"While banks have had a decent run today, I'm not sure it's something that's going to continue for much longer," said Peter Dixon, an economist at Commerzbank. "The macro environment in which were trading is, frankly, dire," he said.
"There are concerns that even though the central banks around the world are finally getting the bit between their teeth and they're starting to cut rates, it isn't enough to prevent what is going to be quite a major slowdown, and that's going to have a major impact on profitability next year."
Sterling hit an all-time low against the euro and a 6 3/4-year trough against the dollar on Thursday afternoon.
Sweden and New Zealand also cut rates earlier in the day.
"Policy makers have changed their views on where we're heading, and they're not far behind the market," said Dixon. "The markets have been given what they think is necessary. It's neither too hot nor too cold."
OIL SECTOR GAINS
Oil shares rose, with BP <BP.L> up 1.1 percent, while BG Group <BG.L> added 6.3 percent.
Miners were the top-weighted losers on the index, with Goldman Sachs downgrading the metals and mining sector. Rio Tinto <RIO.L>, Antofagasta <ANTO.L> and BHP Billiton <BLT.L> all fell between 1.4 and 5.3 percent.
U.S. stocks were slightly lower as the London market closed for the day, as a report showed factory orders plunged for a third straight month in October. Investors looked ahead to non-farm payrolls data due on Friday, the next major gauge of the state of the struggling U.S. economy.
Private equity firm 3i Group Plc <III.L> dropped 8.9 percent after it said it is to reduce its headcount by about 15 percent in response to toughening market conditions.
Insurers were among top gainers in London, lifted by Friends Provident <FP.L>, which soared 6.3 percent on news that potential acquirer Resolution has secured about 500 million pounds ($726.5 million) of investor backing for its stock market listing.
Peers Aviva <AV.L>, Prudential <PRU.L> and Standard Life <SL.L> were up between 1.5 and 4.4 percent.
Reed Elsevier <REL.L> fell 4.5 percent after RBS cut its rating on the Anglo-Dutch publisher to "hold" from "buy".
Stagecoach Group <SGC.L> shed 7.1 percent after Panmure Gordon cut its target price to 160 pence from 205 pence. (Additional reporting by Jon Hopkins and Dominic Lau; Editing by Hans Peters)