Partial Ownership of Property

I have a shop. In 1988, this shop was divided in 2 parts, each having diff. owner. That time i purchased 1 part from the 1st owner and he did sale deed in my name. The 2nd owner leased his part to me as he did not want to sell. In the lease deed done 30 years back it was stated "the second party (me) is at liberty to make any addition or alteration on or in the demised premises and the first party (in this case owner) shall have no objection for the same". Since 1988 i have been running shop of which half part i am owner and half i have on lease. In 1997 the other owner sold this leased part to a 3rd party and since 1997 i am paying rent to the 3rd party on basis of the original 1988 lease . Now the shop needs renovation. My query is if i do renovation can 3rd party object or stop the work by calling police. We are not on talking terms and i deposit rent every month in his account. If i ask him for permission to renovate he will say no. I feel rules of old lease are valid as he bought the half part knowing pre-existence of lease, he has been accepting lease rent since 1997 and lease agreement entered before the acquisition should be bound on the new acquirer i.e. 3rd party. Please advise.