GINA RINEHART hopes to be a ''white knight'' for Fairfax Media, but might sell her shareholding unless she is offered positions on the board without ''unsuitable conditions''.

The mining entrepreneur told the ABC's Four Corners program, via her company Hancock Prospecting (HPPL), that she would be prepared to sell the 18.6 per cent chunk of the company's stock that she holds and consider investing again if her demands were later met.

''Fairfax's largest three mastheads [including the Herald] have been declining in circulation for five years, a long time,'' Hancock Prospecting said. ''Fairfax's share price has also declined … approximately 90 per cent.

''HPPL had hoped that Mrs Rinehart may be viewed by the board as a successful business person and a necessary 'white knight' with mutual interest in a sustainable Fairfax, however unless director positions are offered without unsuitable conditions, Mrs Rinehart is unable to assist Fairfax at this time,'' the statement said. ''HPPL may hence sell its interest, and may consider repurchasing at some other time.''