They are required have to report their interest reduction plans by Aug. 25, and the results must be reported by Jan. 8 next year, it said.
The central bank has cut its policy rates three times since the beginning of the year to bring down loan interest rates amid economic challenges.
Following that, banks have cut their deposit interest rates from more than 10% to around 7.5% now.
Loan interest rates too have come down by 1-2 percentage points so far this year.