Europe's largest carmaker has come under intense pressure from US tariffs, slimmer profit margins from electric cars and above all intense competition in China, the world's largest auto market.Thousands of job cuts have already been announced, but reports say CEO Oliver Blume is now weighing ramping these up to 100,000 as well as potentially closing four factories in Germany.As VW's bosses presented their planned overhaul to the 10-brand group's supervisory board, workers staged protests outside plants and unions warned they were ready to step up industrial action."Whoever takes on the workers is risking a major conflict," Thorsten Groeger, an official from union IG Metall, told reporters at VW's headquarters in the city of Wolfsburg."We will not stand by and do nothing if the company does not change course."At one of the factories said to be earmarked for closure in the eastern German city of Zwickau, about 200 workers joined a demonstration, including one dressed as the grim reaper."This site will not be closed, not against our will -- we will defend it," union official Thomas Knabel told the crowd, who waved banners that read: "United, fighting for our future".'Dramatic situation'"If the plant were to be shut down, it would be the death blow for the region," Denise Tschiersch, who has worked at the factory since 1997 and sits on its works council, told AFP.