Week-long strike to continue
"I would not dare to stand here and tell you we will break our strike on the basis of this incredible supposed offer, which we have already evaluated. It is no offer," said Claus Weselsky.
"We will continue this labour dispute until 9 o'clock on Sunday," he added.
The GDL union launched the seven-day walkout on Monday to back demands for a 5 per cent pay rise and a reduction in the work week to 37 hours from 39 and to negotiate on behalf of other railway workers such as train stewards.
Earlier, Weselsky had told German radio it was possible that the strike, which is causing widespread disruption this week, could be called off ahead of its scheduled ending on Sunday.