Construction of Stairs to encroach 4ft space on road by neighbor

Sir, with due request I would like to inform you that 2 of my neighbors have encroached/blocked the road by extending their elevated stairs 4ft outside on the road side which has reduced the passage path from 12ft to 4ft and it's creating problem to take any materials through that narrow path.it's mentioned in the registry paper that each of the party has to leave 4ft for the road side. I have verbally requested numerous number of times to both the neighbors to remove the extended/elevated 4ft stairs from the road but till date they have not done so. Please suggest legallly to resolve the issue so that I could also be able to construct my house.