The Malaysian carmaker's move could throw a lifeline to Rover which desperately needs a cash-rich partner to develop a replacement platform for its aging 25 and 45 model range.
The current platform will have to be replaced by 2004 when it will no longer be capable of meeting new legislation. John Towers, Rover chairman, said the company had received "one significant approach and two minor developments" in its quest for a partner. His board will start to consider possible collaborations next spring.
A Proton spokesman said: "We have been exploring various avenues to acquire technology and enhance our business, including building strategic alliances with various automakers.
Rover is among the manufacturers we have had discussions with but no definite plans have been made."
Proton is thought unlikely to build cars in the UK. Its current expansion plans are based around the Middle East markets and an assembly plant in Turkey.
More likely would be a platform-sharing agreement for the Rover 25 and 45 replacements and the next generation of Protons. An all-new Proton GX saloon, due in the UK next spring, is underpinned by a development of the Mitsubishi Carisma platform. Development would be undertaken by Lotus and Rover engineers in the UK and Malaysia.
An early joint-venture agreement would allow Rover to hit back at critics who claim the company is not going to survive. Jon Moulton of Alchemy Partnership, whose purchase bid failed, has warned Rover faces financial crisis and would be fighting for survival by March.
In a speech to the Marketing Society, Mr Moulton compared the Government's attempts to provide £150m financial support for Rover to its unsuccessful efforts to save deep coal mining jobs in the UK despite pumping in £75m aid.
His comments were dismissed by Rover which said it was concentrating on moving production of the Rover 75 to Longbridge and did not feel the need to comment.