"That was no subject at all today. Both colleagues are doing excellent work," Matthias Mueller told journalists after the German carmaker published annual financial results.

VW labour bosses earlier this month had accused Diess of breaking promises made under a turnaround plan agreed in November and halted cooperation with brand management on issues including overtime work, cost savings and apprenticeships.

Stadler was meanwhile criticized for his handling of the group's emissions scandal.

(Reporting by Andreas Cremer; Writing by Maria Sheahan; Editing by Arno Schuetze)