A Nostro account is a Vostro account for the bank that opens the account.
In the above example, the account will be called a Vostro account for bank "B". The Vostro account accepts the payments on behalf of the account holder's bank.
If a person deposits money in the Vostro account, it will be transferred to the account holder's bank.
Nostro and Vostro accounts are held in a foreign denomination.
In the case of Sberbank and JSC VTB, these two banks will now be allowed to open Vostro accounts that will accept payments on behalf of the Indian banks, in Indian rupees, by the traders in Russia.