Articles in the Sunday Express had raised questions over MG Rover's financial position. The car maker has refuted the claims and this week pulled its advertising, worth up to £3 million a year, from the Daily Express, Sunday Express and Daily Star.
MG Rover is owned by Phoenix Venture Holdings, which rescued the Rover brand after BMW's takeover of the company two years ago. The Sunday Express suggested it has problems with suppliers unhappy at it not meeting payment deadlines.
Last November, the newspaper group Hollinger began legal proceedings against Express Newspapers over articles in the Sunday Express questioning its profitability.
Express Newspapers refused to comment. However, an Express source said: "This is the sort of thing that crops up from time to time and is something that will be smoothed out in a matter of hours, days or weeks."