Uncle promised to transfer land in my name now denying what can I do

Sir/madam, I had approached my uncle and requested him that I want a piece of land to construct a home. He replied saying that you are like my son and he gave me a permission to construct a house on his land near to his house and that time he said that he will get it land registered on my name after 1 years time. I agreed and constructed a home on my uncle's land by spending more than 30 lakhs. But now my uncle is threatening me saying he will not register that land on my name and he will demolish my home with bulldozer and JCB . So I need legal help in getting this land on my name legally.