General Ledger account wise restriction to see the data

Summary:

General Ledger account wise restriction to see the data

Content (required):

We are implementing for Govt agency and suggesting single ledger instead of multiple ledgers. So business is asking us to restrict the data view/report view by account to users. If i assign General account role and user can see all accounts. I don't have any options to restrict to user to particular accounts.

Govt agency has multiple ministries and created multiple Business units (ministry wise). I am not sure how to restrict this account in GL module level. So user can access only those accounts to view data /balances?