BSNL said its mobile STD and ISD tariffs are already lower than those of private operators, but it is still studying the reduction announced by Airtel and Hutch to see if it needs to cut tariffs, especially in the ISD segment."Our mobile STD rate at Rs 2.20 and ISD tariff at Rs 7.20 per minute is already lower than those of private operators. But there are different tariffs to different countries and wherever we feel these operators are able to match or touch our rates in the ISD segment we will see what can be done to stay in the market," BSNL Chairman and MD A.K.Sinha told reporters on the sidelines of a broadband seminar.There is a very small difference in BSNL and private operators' ISD tarrifs to certain countries, Sinha said, adding "we are studying that and will see what can be done."Yesterday, private mobile operators Airtel and Hutch had reduced long distance tariffs by Rs 1.75 for ISD calls and 35 paise for STD calls. The reduced ISD tariffs, a follow-up of the Trai's new lower ADC regime, would still be more than double of those offered by BSNL.A one minute call from BSNL's mobile phone to the US would cost Rs 7.20 while Airtel and Hutch's postpaid subscribers would have to shell out Rs 14.24 (reduced) per minute from February 1.The pre-paid users of both service providers would pay Rs 15.24 a minute to US, UK, Canada, SE-Asia and SAARC countries, while to Middle East, it will cost Rs 18.24 a minute from February 1.