DB bosses will meet with GDL and EVG representatives on Tuesday to discuss a resolution to the labour dispute that has plagued rail travellers since the beginning of September.
While most of the noise has come from the former, EVG, who have been a silent player until now, are finally threatening to flex their muscles.
EVG head Alexander Kirchner told the Tagesspiegel am Sonntag that DB and GDL cannot carry out separate negotiations.
"To have two collective agreements with varying terms cannot be the solution," Kirchner said. "Then we will also have to stand up for our interests, and if need be, with industrial action."
Kirchner added that he would have "no problem with two identical collective agreements."
A DB spokesperson responded to the report by saying "The only place where we can negotiate a balanced solution is at the negotiations table."
Negotiations in the following days are expected to discuss who has the authority to negotiate pay and conditions for which employees.
While GDL is asking for a five percent raise and a shorter working week, they are also fighting for the right to represent EVG staff.
That would make GDL a much bigger union, as its 2,200 members would be joined by the 17,000 rail workers represented by EVG.
GDL has managed to cripple Germany's transport infrastructure with a series of strikes affecting both commercial and passenger trains, including a 50-hour strike and a 64-hour strike.
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