The Telecom Regulatory Authority of India (TRAI) has issued formal warnings to five cellcos for the deteriorating quality of their services. Last year it asked all of the country’s mobile operators to meet specified quality of service (QoS) levels by the end of the year after complaints by customers over poor call quality sky rocketed. The regulator has now handed Bharti Tele-Ventures, Reliance Infocomm, Tata Teleservices, Spice Communications and BPL Mobile (recently acquired by Hutchison Telecommunications) ‘show cause notices’ for their failure to improve services. ‘It was noticed that at several places the level of congestion of some of the operators was in the range of 80% to 95%,’ the TRAI said in a statement. ‘Being deeply concerned about the deteriorating level of Points of Interconnection (POI) congestion in the networks and also considering lack of efforts on the part of the service providers in effecting timely augmentation of interconnection, it was decided to issue show cause notices.’ The TRAI has given the operators ten days to respond to the notice. Idea Cellular, Hutch, BSNL and MTNL have not been cautioned though the regulator says their service levels remain less than ideal.