Taking a U-turn on its resolve to deport at least 3,000 Bangladeshi migrants every month, India is likely to ‘‘tone down’’ the exercise very soon.Earlier this week, the Union Home Ministry decided to do a rethink on the policy, as it felt the deportation exercise was ‘‘unimplementable’’. The decision is likely to have far reaching implications on states like Assam, Nagaland, Maharashtra and West Bengal, which have already voiced concern over illegal migrants at the recent chief ministers’ conference in Delhi that was chaired by PM Manmohan Singh. The states argued that illegal migration has increased manifold and was posing a security threat. West Bengal Chief Minister Buddhadev Bhattacharya even sought Central intervention, alleging that Pakistan’s Inter-Services Intelligence (ISI) was making use of the porous border.Senior ministry officials said one of the key reasons that forced a rethink on the policy was Bangladeshi Rifles’ persistent denial to take back the migrant Bangladeshis. ‘‘Once the BDR denies to accept illegal migrants, there is very little that India can do,’’ a senior official told The Indian Express. And though the BSF can be asked to ‘‘push back’’ the illegal migrants, the Ministry feels this is a ‘‘inhuman practice’’ and will not be encouraged under any circumstances.Sources said the Border Security Force, responsible for carrying out the deportations, has also raised strong objections. It has argued that looking after the migrants — once the BDR refuses to allow them in Bangladeshi territory — is becoming a huge drain on its resources.Besides, the Ministry, in line with the Congress-led UPA government’s stand, is now treating the issue of illegal migrants as a ‘‘human problem’’. Sources indicated that the parameters of the new policy will be sketched out later this month.