NASHVILLE (AP) - Germany's largest trade union is opening a joint office with the United Auto Workers in Tennessee to promote labor issues at German automakers and suppliers in the southern United States.

Frankfurt-based IG Metall estimates that 100,000 people work for German-owned automotive companies in the U.S. Unlike at their parent companies' factories in Germany, most of the U.S. workers aren't represented by unions.

"IG Metall believes some German manufacturers are exploiting low-wage environments in the U.S. South, where working conditions - including health and safety situations - tend to be challenging for employees," according to a statement obtained by The Associated Press in advance of the official announcement of the new joint office scheduled for later this week.

The move has been in the works for months, but comes against the backdrop of scandal at Volkswagen, which has been the UAW's chief target among foreign automa kers in the U.S. Volkswagen has admitted to cheating on U.S. emissions tests, creating an air of uncertainty at all of its facilities, including its lone U.S. plant in Chattanooga.

The growing cooperation between the UAW and IG Metall is unlikely to be seen as a welcome development among anti-labor Republicans in the South, who argue that a union expansion in the auto industry would hurt future recruiting efforts, especially among Asian companies.

The new office will be located near the General Motors plant in the Nashville suburb of Spring Hill. The goals of the "Transnational Partnership Initiative" include improving wages and working conditions among the numerous German-owned automotive suppliers - and at manufacturers like Volkswagen in Tennessee, Mercedes in Alabama and BMW in South Carolina.

The office also plans to promote German-style works councils to represent both hourly and salaried plant employees.

The UAW has been thwarted for decades in efforts to organize foreign-owned plants in the South, but has come closest at Volkswagen in Chattanooga. An acrimonious union election there last year resulted in a narrow defeat for the UAW, and Volkswagen has since taken a more aggressive stance against the union's efforts to organize a smaller part of the workforce there given the company's struggle to cope with the fallout from the emissions cheating scandal.

Gaining a foothold at plants outside of Detroit's Big Three is seen as key to the UAW's growth potential. While the union has experienced moderate membership gains in recent years, its 403,500 members at the start of 2015 were a far cry from a peak of 1.5 million members in 1979 - before the boom of foreign auto manufacturing jobs moving to the South.

IG Metall, by contrast, started the year with 2.3 million members, and plays a strong role on the German boards of many of the same companies operating in the U.S. without any formal labor representation. U nder German law, half of the seats on supervisory boards are held by worker representatives, while the other half is made up of management and stakeholders.

Gary Casteel, the UAW's secretary-treasurer and director of the union's efforts to organize foreign-owned plants, said in a statement that he was "pleased to be part of the new partnership" with IG Metall in the United States.