The Telecom Regulatory Authority of India has sought an explanation from Mahanagar Telephone Nigam Ltd  for disconnecting cellular operators in Delhi.

MTNL had allegedly blocked calls from cellular users to its fixed line subscribers last week.

While MTNL said the disconnection was due to a technical snag, Communications Minister Pramod Mahajan said he was aware of the disconnection and did not oppose it.

MTNL and Bharat Sanchar Nigam Ltd had earlier threatened to disconnect cellular operators if they did not allow calls from wireless in local loop limited mobility users to pass through.

Over one million cellular users were left stranded last weekend since they could not make or receive calls from fixed line phones.

Meanwhile, basic operators on Wednesday shot off another letter to the telecommunications regulator saying the cellular industry's demand for reciprocal access charges was unjustified.

Officials have hinted the regulator is likely to set an 22cell access charge of 45 paise on basic operators for making calls to a cellular user.