Sept. 3 (Bloomberg) -- Barclays Plc, the U.K.'s third- biggest bank, may need to raise as much as 7.5 billion pounds ($13.3 billion) to bring its capital ratio in line with investment banking peers, Royal Bank of Scotland Group Plc said.

While the London-based bank's so-called tangible common equity is in line with the industry, it's low compared with securities firms, analysts led by Ian Smillie wrote in a research note to clients today. Analysts at Citigroup Inc. in July estimated Barclays may need about 9 billion pounds of capital.

``A deeply ingrained performance-led culture facilitated the generation of 8.3 billion pounds of economic profit over the last four years,'' Smillie said. ``It has, however, also led Barclays to a higher level of balance-sheet gearing than peers, an uncomfortable position in the current environment of financial system de-leveraging and heightened external scrutiny of banks' balance sheets.''

Barclays raised 4.5 billion pounds in a share sale in July to help shore up capital depleted by credit writedowns and to fund consumer-banking growth overseas. The bank's fund raising lifted its so-called Tier 1 capital ratio, which measures a bank's ability to absorb losses, to about 6.3 percent. The bank's ``large and growing equity shortfall'' may mean it has to sell more shares, Smillie said.

Alistair Smith, a spokesman for Barclays in London, declined to comment.

Barclays fell 3.7 percent to 350.25 pence in London trading, valuing the bank at 28.5 billion pounds. The stock has fallen 29 percent this year amid concern about capital adequacy and writedowns at U.K. banks.

More Writedowns

Barclays may post this year a tangible equity ratio, which ignores hybrid bonds, of about 4.8 percent compared to the average of 6.8 percent of its peers, Smillie said. The bank's capital ratio may be eroded by a further 4.7 billion pounds of writedowns and increasing customer bad debts, the analysts said.

Analysts at Goldman Sachs Group Inc. last month estimated Barclays has further potential credit market-related losses of 4.6 billion pounds.

U.K. banks may have tapped the Bank of England's special funding plan for about 200 billion pounds amid the seizure in credit markets, analysts at UBS AG wrote Sept. 1. The central bank introduced its so-called special liquidity scheme in April, enabling British lenders to swap mortgage-backed securities for government bonds.

Tangible equity ratio, a measure of capital widely followed in the U.S., excludes bonds that combine elements of debt and equity. Investors are looking for new ways to judge the strength of banks after financial services companies worldwide wrote down since the beginning of last year almost $510 billion on subprime-related investments.

To contact the reporter on this story: Ben Livesey in London blivesey@bloomberg.net

Last Updated: September 3, 2008 11:53 EDT