Competition over a bus route is putting passengers at risk and causing serious traffic problems, it is claimed.
Concerns have been raised about the 192 Manchester to Stockport service at Piccadilly bus station.
The problem has arisen over congestion at the depot between rivals UK North/GM Buses and Stagecoach.
Manchester City Council and Greater Manchester Passenger Transport Executive (GMPTE) say the situtation is "totally unacceptable".
Both bus companies have increased the number of buses on the route and passengers say the volume of vehicles has made boarding buses dangerous.
A statement from the council and GMPTE said competition between the companies was leading to "acute problems of traffic congestion at Piccadilly and we are concerned about the potential impact on the safety of pedestrians and bus passengers.
"The current situation is totally unacceptable. We are doing what we can to address the problem and ensure public safety."
It added: "We have increased the level of supervision in the area by parking attendants and transport officers. We are calling on the Traffic Commissioner to use her powers to resolve the situation without delay."
Ray Cossins, Commercial Director of Stagecoach Manchester, said it had always observed the Manchester CityPLAN agreement - the city centre code of conduct for bus operators - to avoid unnecessary congestion.