MTNL and BSNL have crossed swords over collection of access deficit charge (ADC) by the former from other operators and passing it on to the latter.MTNL had issued a circular on January 31 to all the operators over the implementation of the interconnection usage charges (IUC) on its network. BSNL has raised objection, and has asked MTNL to modify the circular in accordance with Trai's regulations."On examining the mentioned circular, it has been observed that MTNL is collecting only transit charges for all intra-circle and inter-circle calls originating from basic and cellular service providers, and the applicable ADC on these calls is not being collected by MTNL," BSNL said in a letter to MTNL."This is not in conformity with Trai's Telecom Interconnection Charges Regulation of October 29, 2003," BSNL said.The new IUC of Trai, which came into effect from February 1, 2005, is an amendment of previous IUC regulations of Trai. As per the new regulation, BSNL says in the letter "ADC is to be received only by BSNL"You are therfore requested to modify your implementation of IUC regulation in the MTNL network circular accordingly for making provision for collecting applicable ADC, and pass on the same to BSNL in compliance with regualtion."