Volkswagen aims to cut costs by 20% by 2028 as competition from Chinese carmakers intensifies.
Reports say plant closures are among the options under review.
Chief executive Oliver Blume and finance chief Arno Antlitz outlined the plan to senior managers.
The goal is to secure sustainable profits despite falling sales and high production costs.
The company already launched a major restructuring that will reduce 35,000 jobs by 2030.
Those measures are expected to deliver billions in annual savings.
Volkswagen said it will comment further when it presents results on 10 March.
It added that earlier reforms have already generated double-digit billion-euro savings.
The pressure for change comes as the EU trade deficit with China continues to grow.
German carmakers remain deeply dependent on the Chinese market through joint ventures and local manufacturing.
