Volkswagen allegedly is trying to coerce factory workers at its Chattanooga, Tennessee, plant to join UAW.

United Auto Workers has been pushing to unionize Volkswagen's Chattanooga, TN plant, and Volkswagen seems to be open to the idea - the two parties already have discussed an employee "works council" for the factory, which would require UAW organization - but the automaker says it will only recognize UAW if employees approve the move via a formal secret ballot. But now some workers are claiming that VW is coercing them into joining the union, The Tennessean reports.

Specifically, four workers at the plant, which builds the Passat, filed a charge with the National Labor Relations Board alleging that a senior member of VW's German management said the factory might not get another vehicle to build - a future three-row crossover - unless workers agree to join the union. The workers say that if VW refuses production of a vehicle at the plant because they don't join UAW, it interferes with their right "to choose whether or not to engage in self-organization to form, join, or assist labor organizations," The Tennessean reports. That's illegal under federal law.

In the Southern US, foreign automakers and their factories have traditionally rejected UAW organizing drives, such as Nissan and its Smyrna, Tenn. plant, so VW's seemingly pro-union stance goes against the norm. That coupled with Chattanooga workers' hesitancy to join UAW makes the situation unique, and this latest allegation adds a dose of complication.

Making matters more urgent, the Chattanooga plant is competing with a Mexican plant to build the aforementioned crossover, and a decision on its production is expected by the end of the year.

UAW says it has gathered signatures of support from more than half of the plant's workers, and it wants VW to recognize the union without a formal vote. But, as stated above, VW says it wants a formal secret ballot cast before it recognizes the union.

Update: A previous version of this post incorrectly stated that Nissan's Canton, Miss. plant had rejected a UAW organizing drive. The text has since been corrected.