On the eve of today's crisis meeting, Klaus Volkert, a supervisory board member representing the powerful IG Metall union, said Mr Piech's 'bellicose rhetoric is totally out of place, heating up the media discussion'.
Mr Piech's xenophobic outbursts - in which he has accused General Motors of waging a war, replete with dirty tricks, to destroy VW - also met with expressions of dismay from other German business leaders.
Mr Volkert has exposed widespread dissatisfaction within the supervisory board with Mr Piech's attack on GM, which is pursuing VW's number two, Jose Ignacio Lopez de Arriortua, on suspicion of industrial espionage.
'VW's public relations work in this affair has been anything but felicitous,' Mr Volkert said.
Mr Volkert called upon Mr Lopez to help the state prosecutor investigating GM's accusations of document theft against him, so that the affair could be closed before it did lasting damage to the firm.
A company spokesman would neither confirm nor deny that Mr Lopez would be called before the board to support earlier assurances that the espionage claims against him were not true.
The board is also expected to ask Mr Piech how he expects to meet his pledge of turning around VW's heavy losses by the end of the year. Analysts are predicting annual net losses of between DM400m and DM800m.