* FTSE 100 seeks 6th straight session of gains
* Defensive issues pull index higher
* Commods, banks weaker after recent gains
By David Brett
LONDON, Sept 18 (Reuters) - Britain's top share index hauled itself back into positive territory by midday on Friday, searching for a sixth straight session of gains, as investors sought comfort in defensive issues and took profits in commodities and banks.
At 1114 GMT, the FTSE 100 was up 4.95 points at 5,168.90, having earlier reached a new 2009 peak at 5,179.14, after closing 0.8 percent higher on Thursday at its highest level since late September last year.
"There is clearly a conflict going on right now with some traders feeling it is time to book profits, but the sentiment is far from universal," said Anthony Grech, market strategist at IG Index.
Figures from Britain's Office for National Statistics, which said the public sector posted a net cash requirement of 10.379 billion pounds in August, failed to deter investors.
The figure was lower than the 12 billion pounds expected by analysts but still twice the level of the same month a year ago.
"The bubble doesn't really show any signs of bursting," said David Buik, senior partner at BGC Partners.
Defensive stocks found support as investors turned back to equities that have lagged the broader market rally and are generally seen as "safe havens".
Beverages, tobacco and pharmaceutical issues were the top performers.
Drinks maker Diageo and brewer SABMiller rose 1.3 and 1.5 percent respectively, with SABMiller supported by a UBS upgrade to "buy".
British American Tobacco added 0.6 percent, whilst GlaxoSmithKline, AstraZeneca and Shire gained 0.2-2 percent.
GlaxoSmithKline is in talks to buy a 5 percent stake in Indian drug maker Dr Reddy's Laboratories in a deal likely to be valued at $150 million, the Economic Times reported on Friday, citing sources privy to the development.
Real estate firms Hammerson and British Land were up 2.6 and 0.6 percent respectively, underpinned by upgrades from Societe Generale, which raised the former to "hold" from "sell" and the latter to "buy" from "hold".
British Land is poised to conclude the long-awaited sale of half of its Broadgate office complex to private equity firm Blackstone, the Financial Times reported on Friday.
Kingfisher climbed 3.6 percent, topping the blue-chip leaderboard, after the home improvements retailer's strong first-half results a day earlier prompted a round of price target hikes by brokers.
BANKS, OILS WEAK
Banks were mostly lower, with Lloyds Banking Group down 0.9 percent, while Standard Chartered, Royal Bank of Scotland and Barclays dropped 0.5 to 1.1 percent. Only heavyweight HSBC provided some support for the sector, up 0.6 percent.
Lloyds Banking Group said on Friday it was in talks over scaling back or cancelling its participation in a state-backed scheme to insure it against credit losses.
The Lloyds situation also led to weakness in sterling as traders found sanctity in the more defensive U.S. dollar.
Energy stocks were weak as crude prices dipped below $72 a barrel on Friday. BG Group fell 1 percent, while BP dropped 0.4 percent and Cairn Energy shed 2.3 percent.
A broker downgrade weighed on Tullow Oil, off 3.1 percent, with Citigroup cutting its recommendation on the oil explorer to "hold" from "buy" after strong gains over the past week and oil find news on Thursday.
Utilities were also lower with Pennon, Severn Trent and Centrica down 1.6-2.1 percent.
With little news scheduled in the United States on Friday, stock index futures pointed to a quiet open on Wall Street, with the S&P 500 and Dow Jones futures flat and Nasdaq 100 futures up 0.1 percent. (Editing by Jon Loades-Carter)