Trade Secretary Patricia Hewitt has sent a team of top officials to Shanghai in a last-ditch bid to save MG Rover.

The move reflects Ministers' frustration over the Birmingham car manufacturer's lack of progress finalising an agreement with the Shanghai Automotive Industrial Corporation.

It has the personal backing of Prime Minister Tony Blair and Gordon Brown, the Chancellor.

MG Rover first announced plans for a partnership with SAIC last June but negotiations over the joint venture agreement, which the company needs to survive, have continued to drag on.

The Government is offering MG Rover, which currently employs 6,000 people at its Longbridge factory, a #100 million bridging loan to ensure it can continue trading until the Chinese step in.

However, it is also demanding that MG Rover's directors make a personal contribution of several million pounds towards the loan.

Officials have already begun talks with the Chinese in Shanghai and these will continue over the weekend, which is being seen as a critical time for the future of the car maker.

The Department of Trade and Industry has also drawn up contingency plans to help MG Rover employees and suppliers, and the West Midlands economy in general, in the event that no agreement can be reached and the company folds.

The situation is considered so serious that Ministers are offering to brief Conservative and Liberal Democrat front-benchers on developments, as well as Mike Whitby, the Tory leader of Birmingham City Council, and his Lib Dem deputy John Hemming.

Ministers hope to avoid the MG Rover crisis becoming a political football as Westminster braces itself for a possible General Election.

A Whitehall source said: "Throughout this process, the Government has done all it can to help support the joint venture between MG Rover and SAIC.

"This is, however, a commercial deal between two companies and, even with our offer of a bridging loan, its success is not guaranteed.

"We can, however, guarantee that should this venture fail the Government will provide support and financial assistance to the workers, their families and communities affected."

The DTI earlier attempted to arrange a meeting bringing the Chinese and MG Rover together in London, but this fell through because the Chinese were either unable or reluctant to attend.

The talks in Shanghai follow repeated requests from the DTI for discussions.

The planned bridging loan is designed only to tide the company over until SAIC can inject more money.

It will have to be re-paid, because European Union state aid laws forbid cash pay-outs to help ailing businesses.

However, the loan involves an element of risk to the Government, as MG Rover is unlikely to have the cashflow required to pay it back if the Chinese walk away.

The decision to ask MG Rover directors to share some of the risk has been prompted partly by the knowledge that they have enjoyed generous financial benefits since buying the business from BMW in 2000.

If the Chinese deal collapses, Ministers are expected to help MG Rover seek an alternative partner or a buyer.

However, it is recognised that the manufacturer's prospects would be bleak.

Accounts for 2003 showed the car firm's parent group, Phoenix Venture Holdings, lost #77 million - and the company has warned losses will be higher for 2004.

Even if an agreement is reached, significant job losses are expected at Longbridge and the DTI is drawing up plans to help employees find new work or training.

The proposed joint venture will see the creation of two businesses based in China and the UK, both of which will be majority owned by SAIC.

Earlier this week, MG Rover insisted negotiations with SAIC had been completed and contracts were being drawn up.