NEW YORK - US PRESIDENT George W. Bush on Wednesday acknowledged bitter debate in the US Congress over his bailout for troubled banks but predicted a strong package 'when it is all said and done.'

Meeting with leaders from the Western Hemisphere to promote trade accords, Mr Bush declared 'I know they're going to want to hear about the rescue plan that we have submitted to the Congress.'

'They can see our legislative process is full of give-and-take, that there's ample debate, but I am confident that when it is all said and done, there will be a robust plan. And there needs to be,' said Mr Bush.

Mr Bush postponed attendance at a Republican political fundraiser in Florida, and he was reportedly considering a speech to the nation on his administration's embattled US$700 billion (S$986 billion) rescue plan.

US lawmakers were digging their heels in on Wednesday against the bailout, setting the scene for a fierce showdown on Capitol Hill watched anxiously by markets around the globe.

Federal Reserve chairman Ben Bernanke and Treasury Secretary Henry Paulson were facing another day of testimony, after Tuesday's cold-shoulder reception by senators balking at a swift passage of the bailout.

The duo argued that failure to pass the emergency measure quickly would put the entire US economy at risk, but lawmakers appeared unwilling to let Wall Street off the hook at the massive expense of US taxpayers, while the FBI reportedly launched a probe of failed banks and mortgage giants.

'What they have sent to us - this is not acceptable,' Democratic Senator Christopher Dodd, chairman of the Senate Banking Committee, told reporters after Mr Bernanke and Mr Paulson testified.

Defending the package, White House spokesman Tony Fratto said on Tuesday that the bailout had been 'months' in the making but insisted that lawmakers should pass it 'this week'.

'This was not a program that was conceived of, or put together, hastily. There was an enormous amount of analysis and debate and discussion before we came forward with this programme,' said spokesman Tony Fratto.

'Some of the policy staff have had months to think about what a programme like this would be like and how it would work. Others have had at least weeks to think about it,' he told reporters on a conference call.

'We do need to get it done quickly and urgently and would oppose efforts to delay it,' the spokesman said. 'I think we want to be confident that it will get done this week.'

In a subsequent email exchange, Mr Fratto declined to say when the administration first began internal discussions on the mammoth plan, but told AFP: 'It shouldn't come as a surprise that we think about contingencies.' -- AFP