* FTSE rises 0.3 percent in thin trade
* Oils, miners lead; banks reverse early gains
* Investors digest grim GDP data
By Rebekah Curtis
LONDON, Dec 23 (Reuters) - Britain's FTSE 100 <
> rose 0.3 percent by mid-session on Tuesday, led by oils and miners but with volumes petering out in the last full trading day before the Christmas holidays.At 1140 GMT, the FTSE 100 was up 11.75 points at 4,260.91, having closed 0.9 percent lower on Monday. The index is on track for its worst ever year, having shed a third of its value year-to-date in a credit crisis that has dragged several major economies towards recession.
Oil shares rebounded from losses the day before, with BP <BP.L>, Royal Dutch Shell <RDSa.L> and BG Group <BG.L> adding between 0.4 and 1.1 percent.
Miners bounced too, with Xstrata <XTA.L>, Rio Tinto <RIO.L> and Anglo American <AAL.L> up between 0.8 and 3.1 percent.
"The volumes are pathetic, so there's nothing there to grab hold of," said Howard Wheeldon, senior strategist at BGC Partners. "Markets are moving around in an aimless direction and there is nothing to read into whether we end the day up or down," he added.
"We've got the lull before the storm. The first three months of next year are going to be torrid out there in the UK. We've got to batten down the hatches for maybe 8 months and we'll start to see some beneficial signs appearing in the final quarter of next year."
GRIM GDP
Official data showed Britain's economy shrank by more than previously thought in the third quarter, and for the first time since the early 1990s, raising concerns the UK is heading into a deep recession.
"There's nothing on the macro front to suggest there's any let-up in the difficult conditions," said Jeremy Batstone-Carr, head of private client research at Charles Stanley.
"Some of the tail winds from 2008 are likely to stretch into 2009 ... Many imagine that Q1 will be very tough," he said.
Among data due from across the Atlantic investors are expected to eye U.S. GDP figures and U.S. existing home sales data.
U.S. blue chips <
> were expected to edge higher, having lost 0.7 percent overnight depressed by gloomy corporate news, while Asian markets retreated in sympathy. Japanese markets were closed Tuesday for a public holiday.Back in London, the banking sector lost traction as HSBC <HSBA.L> dropped 1.5 percent and Standard Chartered <STAN.L> shed 0.7 percent. But Royal Bank of Scotland <RBS.L> rose 3.1 percent and Lloyds TSB <LLOY.L> gained 1.9 percent.
Rolls-Royce <RR.L> was 2.2 percent higher after it announced a $575 million deal with Etihad Airways to supply and maintain Trent 700EP engines for eight Airbus <EAD.PA> A330 aircraft.
Centrica <CNA.L> added 1.1 percent. The Financial Times said the British Gas owner hopes to agree a deal by the end of next month to take a 25 percent stake in British Energy for about 3.1 billion pounds ($4.59 billion), after France's EDF <EDF.PA> was given the go-ahead Monday by Brussels to buy the owner of Britain's nuclear power stations. (Editing by Victoria Bryan)