Fears are mounting that many Wall Street banks and financial firms will refuse to participate in the US government's $700bn bail-out package, leaving global markets and world economies in a perilous state for months to come.

'There is a growing feeling that banks ... might instead decide to tough it out,' said Thomas Caldwell, chairman and CEO of Caldwell Financial, a $1bn-plus fund manager.

For the past two weeks all eyes in the market have been focused on US Congress and its attempts to pass Treasury Secretary Henry Paulson's bail-out package - a bill to allow the US government to buy up to $700bn of toxic mortgage-related assets from American banks, which would in theory free the credit markets and set the gears of global commerce spinning once more.

Last Monday, after the bill was thrown out by the House of Representatives, more than $1 trillion was wiped off the value of US stocks as the market was gripped by panic. The bill was passed on Friday afternoon, however, after the inclusion of $149bn of tax breaks and strict rules for participating banks.

But Wall Street analysts, believe the addition of so many terms to the bill might deter potential participants.

One of the least attractive elements is a section designed to curb executive pay at banks that participate in the bail-out package. These include limiting stock-related pay and banning 'golden parachutes' for executives.

'I think this hodge-podge of regulations and rules will be enough to put many [chief executives] off participating,' Caldwell said.

Sources close to Goldman Sachs and Merrill Lynch indicated the banks might choose not to participate in the bail-out as there is a growing view on Wall Street that the market may be bottoming out.

Analysts also believe that the mere presence of the government as buyer of last resort will be enough to get credit markets moving again, and that a large number of banks would not need to take part for the legislation to succeed.

Wall Street ended its worst week in seven years with another tumble on Friday. The Dow Jones Industrial Average closed down more than 157 points on Friday at 10,325.38.