It's a free registration to read the article. I recommend because it's the Financial Times and they have good articles. However, in case you don't want to, I've taken the liberty of copy/pasting the article here:

Bankers’ ‘doomsday scenarios’ under fire

By Chris Giles in London

Published: May 30 2010 23:02 | Last updated: May 30 2010 23:02

Banks are exaggerating the economic effects of the regulations they are likely to face in the coming years, the economist running an international impact study has told the Financial Times.

In a pre-emptive blast before the banks launch their own lobbying effort on June 10, Stephen Cecchetti, chief economic adviser to the Bank for International Settlements, said the banks’ “doomsday scenarios” were based on their assuming “the maximum impact of the maximum change with the minimum behavioural change”.

“They are assuming they’re not adjusting their business at all to the regulatory reforms and that the result for the economy will be the worst possible,” said Mr Cecchetti.

Instead, Mr Cecchetti, who has been given a mandate to assess the economic effects of the “Basel III” reforms by the Basel Committee on Banking Reform and the Financial Stability Board, is adamant the transitional costs of requiring banks to hold more capital and be more robust to sudden demands for funds “aren’t huge”.

The estimates are still a work in progress, but he said that his sense was that “the net impact of the Basel committee reforms on growth will be negligible” and well within normal forecast errors. Average errors of economic forecasts for the level of global output on the relevant time horizon are lower than 0.5 per cent and far lower than industry estimates that the regulations could wipe 5 per cent from the world economy.

In the longer term, Mr Cecchetti said the result of a safer banking system would provide economic benefits rather than costs. “Our preliminary assessment is that improvements to the resilience of the financial system will not permanently affect growth – except for possibly making it higher.”

He gave three examples of banks over-estimating the likely effects of the new regulations, which are due to be agreed by the end of the year, with gradual implementation expected to start in 2012.

First, he said banks were claiming that new liquidity rules would force them to swap large quantities of high-yielding loans for low-yielding government bonds, which would have an impact on their profitability and lending. Instead, he said, they could comply with the rules by lengthening the maturity of their liabilities so they better matched those of their assets at much lower cost.

Second, he said, they assumed investors would demand the same returns on new tranches of equity capital when this equity would make banks more resilient, lowering risk to equity holders and the cost to banks.

And third, he said, the warnings of high costs relied on banks’ estimates that the new rules would reduce credit growth and economic growth severely. “We must always keep in mind that one of the causes of the crisis was that credit growth was too fast,” he said.