Germany's "Mittelstand" of small and medium-sized firms (SMEs) could lose billions of euros if the UK is shut out of the single Market, an industry representative has warned.
Mario Ohoven added that negotiations should be "guided by economic sense and not by political ideologues".
The remarks diverge from the position taken by other leading German voices.
In September last year, the head of the BDI, a powerful German business lobby whose members are larger companies, told the BBC it was "better to have a hard Brexit that works".
German politicians have almost unanimously underlined that the UK cannot have unfettered access to the single market unless it allows for the free movement of EU citizens.
In her letter to the EU last week, Theresa May said the UK would "not seek membership of the single market" in the upcoming negotiations.
BBC News.
