Government spokesman Mobhare Matinyi said the allegations were false
In bi-annual projections, the bank said it expected the economy to expand by 1.0 percent next year, compared with its June estimate of 2.0 percent.
It also cut its prediction for 2014 growth to 1.4 percent from 1.9 percent in June.
It said it saw gross domestic product (GDP) increasing by 1.6 percent in 2016, trimming its forecast from 1.8 percent in June.
"However, there is reason to hope that the current sluggish phase will prove to be short-lived," Bundesbank President Jens Weidmann said in a statement.
He also added that opportunities abroad would likely increase again next year.