* Banks reverse earlier gains to trade down; Lloyds slumps
* RBS rebounds after Monday's slides
* Drugmakers and tobaccos in demand
By Dominic Lau
LONDON, Jan 20 (Reuters) - Britain's leading share index ticked up by midday on Tuesday, led by drugmakers, tobacco firms and oil producers, but banks gave up earlier gains to trade down as investors remained bearish on the beleaguered sector.
By 1156 GMT, the FTSE 100 <
> was up 6.86 points, or 0.2 percent, at 4,115.33, after losing 0.9 percent on Monday. The UK benchmark is down 7 percent this month after plunging more than 31 percent last year -- its worst annual drop since its launch in 1984."The whole banking sector is collapsing," said Jawaid Afsar, a trader at Securequity. "There is just no one out there who wants to buy the banks. Quite frankly there is too much concern about writedowns and possibility of nationalisation."
Lloyds Banking Group <LLOY.L> lost one-third of its value to touch its lowest in more than 20 years on continuing woes in the banking sector. A spokesman from Lloyds said the bank continued to trade satisfactorily since its last update.
"The merger of HBOS and Lloyds TSB into Lloyds Banking Group creates the weakest of the UK banks in terms of capital, funding and problem loan book areas," Merrill Lynch said in a note. "We see a capital deficit based on our stress test work."
Barclays <BARC.L> slid 9.7 percent, HSBC <HSBA.L> shed 3.2 percent and Standard Chartered <STAN.L> lost 3.5 percent.
Royal Bank of Scotland <RBS.L>, however, rebounded 7.8 percent after losing two-thirds of its value on Monday.
The pound fell over 3 percent to a 7-1/2 year low against the dollar below $1.40 as banking sector woes battered the currency.
"The (UK) measures ... will not restore confidence in the sector and given the extent of economic headwinds we retain our cautious view on the UK banks," Deutsche Bank said in a note.
"With ongoing credit quality and capital risks for Lloyds and RBS in particular we believe these stocks will continue to trade materially below tangible book value and we maintain our sell on Lloyds."
Britain threw its troubled banks another multi-billion pound lifeline by allowing them to insure against steep losses and guaranteed their debt to stop the credit crunch pushing the economy deeper into recession.
Across the Atlantic, Barack Obama takes over as U.S. president with hopes riding high that he can conjure up a rescue that will jolt the world's biggest economy back into life and contain the financial crisis ravaging financial markets.
Drugmakers, deemed defensive by investors, were in demand, with GlaxoSmithKline <GSK.L> up 1.6 percent, AstraZeneca <AZN.L> rising 2 percent and Shire <SHP.L> gaining 2 percent.
Cigarette makers rose as investors sought a relatively less risky area to park their money. British American Tobacco <BATS.L> and Imperial Tobacco <IMT.L> put on 3.3 and 3 percent respectively.
Oil producers were also in positive territory, with BG Group <BG.L> up 1 percent and Royal Dutch Shell <RDSa.L> advancing 1.6 percent. (Editing by Jon Loades-Carter)