John Towers, the former Rover chief executive who is plotting to buy the carmaker, wants to take the Cowley plant as well as the Longbridge operation, it has emerged.

Mr Towers has told BMW that he wants to keep together the group in full, minus the Land Rover operation, which is going to Ford. Sources close to the bid, which is expected to be launched in the next few days, suggest that he is looking to offer about £800 million, though he still needs to seal some final financial backing.

Mr Towers believes that the new Mini and the rights to the new R30 model are keys to the success of a mass production Rover operation. It is thought that BMW executives in the UK have shunned the idea. However, a spokesman in Munich yesterday said that nothing would be ruled out until a full bid was on the table.

BMW has announced plans to scale back production at Cowley but at present it plans to make the new Mini there and also to produce the Rover 75 for the first bidder for Rover, the venture capital group Alchemy Partners .

It is believed that Mr Towers is attempting to secure substantial financial support from the Government.

Separately, the T&G hit out at BMW for refusing to negotiate over the redundancies, which are expected if Alchemy wins the bid race. Unions also fear there could be up to 4,000 redundancies among the 10,000 planned to be retained by BMW.