Plans by Germany’s ThyssenKrupp and Tata Steel, subsidiary of the Indian-based Tata industrial giant to combine their European steel operations may hinge on Tata Steel’s plant in IJmuiden, Reuters new agency reported on Thursday.

The merger faces renewed opposition from German unions which claim the companies’ labour agreement in the Netherlands goes too far in protecting work and operations there, Reuters said.

Last month Tata Steel guaranteed its Dutch division could continue to operate as an independent company within the planned joint venture with ThyssenKrupp, with control over its own profits and an independent supervisory board.

The plant in IJmuiden would remain a ‘fully integrated steel company’, Tata Steel Netherlands said.

The IJmuiden plant was started as Hoogovens in 1918, but merged with the larger British steel to form Corus in 1991. Tata Steel bought Corus in 2007 renaming it Tata Steel Europe.

‘It is not acceptable that only we in Germany are to be responsible for the risks of the joint venture and the Dutch entity is dodging responsibility,’ ThyssenKrupp supervisory board member Tekin Nasikkol told Reuters. German employees would not accept this, he said.

ThyssenKrupp and Tata Steel last year announced plans to combine their European steel operations which would involve up to 4,000 job cuts. Local media said at the time 2,000 jobs could be lost at the former Hoogovens plant.