25 years back banks were not operating in competitive environment. They were operating like Sarkaari daftars and if Locker facility is given to customers there is nobody to question what other business you got from that fellow who was given locker facility. It goes without saying that anyone who needs a locker must have been rich person and banks see them as source of increasing business. When there was no competition bank managers didn't bother about this. Someone wanted locker they provide facility and forget that fellow. Nowadays they see business in these fellows. If someone comes for locker they demand to open FD account with them.
There is also reason for this apart from business. Bank rented locker, some poor fellow kept some property documents and died without information to near and dear about locker . ..how bank will collect rents?
So they need an FD that generates interest so that they can transfer interest on it to rent received on locker account. As it serves both purposes as mentioned above nowadays it has become mandatory for them to demand FD from locker holder. One fine day they realize that for lockers given 20 years back they didn't take FD. So they ask someone like you to keep FD.
Now the question is whether it is as per any RBI regulation or not. The answer is these are internal policy matters of bank relating to improvement of business. Every individual bank may have a policy of its own. But in your case obviously when locker facility was granted there was no such policy that's why they had not taken FD then itself (while opening locker account).
Now they are not supposed to enforce their new policies on old customers. It is somewhat like expost facto law.
However my advice to you is don't go on warpath with bank just because you have a point to contest because that will affect Customer-banker relationship.
