Rail workers are being told to take German lessons as part of their training course for operating new track equipment.
Staff on a recent course in Kent were told they had to learn a series of German phrases relating to instructions on track equipment, the Rail Maritime and Transport union (RMT) said.
Officials said the development comes as German rail giant Deutsche Bahn looked to "tighten its grip" in the UK through the acquisition of the Grand Central franchise, opening up an opportunity to use EU rules to start running services on the east and west coast - and with the continuing row over the proposed award of the Thameslink fleet contract to Siemens at the expense of UK train building at Bombardier in Derby.
The RMT said it would be simpler and safer to get the equipment re-programmed with a translation into English rather than placing the responsibility to learn German on the workforce.
RMT general secretary Bob Crow said: "From Siemens involvement in the betrayal of Bombardier through to Deutsche Bahn taking over the UK's Grand Central franchise last week, EU diktat is driving a German corporate takeover of Britain's railways.
"Profits that could be invested in our services are instead spirited out of the country without touching the sides.
"It is extraordinary that the German companies can't even be bothered to translate their safety instructions into English and instead UK rail workers have to take responsibility with these crash courses in O-level German."
