BERLIN, Oct 7 (Reuters) - German industrial output dropped by far more than expected in August due to supply chain disruptions that are holding back growth in Europe’s biggest economy, official data showed on Thursday. The Federal Statistics Office said industrial output fell by 4.0% on the month after an increase of 1.3% in July. A Reuters poll had pointed to a decline in August of 0.4%. “Manufacturers continue to report production constraints due to supply shortages of intermediate products,” the Office said in a statement. Writing by Paul Carrel Editing by Riham Alkousaa Our Standards: The Thomson Reuters Trust Principles.