refunding money from builder

I have paid about Rs.17 lakhs in 2012 to a builder who promised to give possession of my apartment by November 2014. An agreement for sale has also been signed. However, till now the project has not started. When I asked him to return the money saying that I am not interested in the property due to the delay, he is refusing to give me back the money (paid through cheque to him). How can i get this money back from him? Any amount of requesting has failed to get results. Thanks and regards