Union leaders are seeking urgent talks with aerospace giant Airbus amid fears that thousands of jobs could be axed.
It is believed the workers may be laid off because of the possible collapse of a huge defence project.
The future of the Airbus A400M transport aircraft is said to be in doubt after the German government raised problems over its pledge to take 73 of the aircraft.
Eight countries committed themselves to the wide-bodied aircraft last year. But the German finance ministry is reported to have warned that legal budgetary requirements had not been fulfilled and would not be ready until the end of the month.
Germany has been hit by recession and the government is having problems raising enough cash to fund the project.
