DETROIT (Michigan) - AUTO workers on Wednesday stood by ailing US carmakers, vowing to make tough sacrifices in exchange for a massive US$34 billion (S$51.8 billion) government bailout to save the vital industry from collapse.

As the White House said it was reviewing the Big Three automakers' radical restructuring plans, union boss Ron Gettelfinger said the union was 'willing to take an extra step to move this along'. He said the United Auto Workers (UAW) was prepared to modify the union's contract and delay billions in payments to a health care fund as its part in helping to secure the future of the core industry.

'Are we going to blame the auto workers, who are by the way 10 per cent of the cost of automobile,' Mr Gettelfinger asked. 'Or are we going to take a look at what's happened to our economy, to the housing crunch to the Wall Street bailout and the failures on Wall Street?'

On Tuesday Ford, General Motors and Chrysler unveiled plans for a radical restructuring of their companies to convince Congress that they can achieve long-term viability with a total of US$34 billion in loans.

GM and Chrysler warned they needed billions of dollars within a matter of weeks if they were to survive a perfect storm of a global credit crisis, falling demand for large vehicles and a global economic slump.

All three put forward plans to invest billions in advanced technology, shift their product mix towards more environmentally friendly vehicles and slash operating costs.

At stake are millions of jobs, many of them in Detroit, the heart of the US auto industry, but also in secondary industries around the country.

The fate of the key auto industry is shaping up to be the first major test of the incoming administration of president-elect Barack Obama, who has warned he is not prepared to write the companies a blank check.

Mr Obama said he wanted to hear what the automakers had to say at congressional hearings on Thursday and Friday before committing himself to any bailout.

'We should maintain a viable auto industry,' he told a press conference on Wednesday.

'But we should also make sure that any government assistance ... is based on realistic assessments of what the auto market is going to be and a realistic plan for how we're going to make these companies viable over the long term.'

The current White House said it was reviewing the three different plans, but cautioned not to expect any decisions in the coming days.

But officials said the current administration had not ruled out that aid to troubled US automakers might total more than US$25 billion in an existing loan programme it had insisted was the best rescue plan.

'I'm not ruling anything in or out,' said spokesman Dana Perino. Lawmakers turned away the three chief executives empty-handed last month and charged them with coming up with proper plans on reshaping their companies.

They were roundly criticised for letting their iconic brands crumble in the face of competition from foreign transplants, whose US plants operate at much lower costs, and failing to develop smaller fuel-efficient cars.

There was also anger that all three had flown to Washington for the hearings in separate corporate jets - more proof of the excesses of the CEO lifestyle. So on Wednesday the three auto chiefs were driving to the capital in fuel-efficient hybrid vehicles for Thursday and Friday's hearings.

Under their new plans, Ford and GM will get rid of their company airplanes and all three chief executives will work for salaries of one dollar a year.

Ford said on Tuesday it might pull through on its own and return to profitability by 2011, but asked for a US$9 billion line of credit in case the economy worsens or one of its competitors goes bankrupt.

GM asked for US$4 billion this month and another US$14 billion next year. Chrysler said it needed US$7 billion by Dec 31.

GM, which is considered to be at the greatest risk of collapse, offered the most radical plan on Tuesday.

It said it will reduce its US workforce by nearly a third from the current level of 96,537 people to between 65,000 and 75,000 salaried and unionised workers by 2012 and cut the number of US plants from 47 in 2008 to 38 in 2012.

The world's second largest automaker said it will also 'review' the future of its Saab and Saturn brands.

Industry data out Tuesday showed US auto sales dropped 37 per cent last month, as total US sales fell to 746,789 from nearly 1.2 million vehicles in November 2007.