Builder still not started construction even after 3 years what to do.

Sir, I had booked a flat three years back and entire booking amount of 5 lakhs was paid by cheque. Builder had given in writing that he had received the cheque (also mentioning the cheque numbers). In terms and conditions, it was mentioned that amount will be refunded fully (without interest) if due to any problem construction has been cancelled. But even after 3 years he had not started construction. Once I enquired in CIDCO, I came to know that the plot itself has not been completely acquired by builder as some dispute between him and local farmers is going on. So I cancelled the booking & informed to refund the money within 3 months. Even after 5 months, he has returned the money,citing the reason that he is in financial crisis and will refund the money as soon as possible. Can I claim interest for the amount for the past three years if I go to consumer court?