Rolling strikes hit nine of auto giant Volkswagen's plants across Germany for the second time this month, as the Volkswagen workforce protests painful proposed cuts at Europe's largest carmaker. Monday's strikes ratchet up the pressure on management on the same day that the fourth round of collective bargaining negotiations over pay cuts and threatened factory closures got under way on Monday in Wolfsburg,

Tens of thousands of Volkswagen workers walked out on Monday in the second round of strikes in an escalating conflict between unions and management over the German carmaker's drastic savings plans.

The IG Metall workers union said it would increase the pressure ahead of a fourth round of negotiations in the labor dispute. The union accused VW management of 'slipping layoffs under the Christmas tree.

Workers at German factories for carmaker Volkswagen are to go on strike from Monday over plans to cut thousands of jobs, union IG Metall said Sunday.

By Victoria Waldersee and Christina Amann WOLFSBURG, Germany (Reuters) - Volkswagen workers ramped up pressure on its management with further strikes at the carmaker's German sites on Monday, as a fourth round of talks was set to begin in an increasingly bitter standoff over wage cuts and plant closures.