We are rewiring a house. The neighbour's gas pipe passes, uninsulated, through the house due to what seems like a bit of suspect extension building last century. I feel that, as this is an extraneous conductive part, it should be bonded to the earth terminal of the installation (it is within touch distance of a socket outlet) although by bonding it, earth faults in the neighbour's property will affect this one and vice-versa (assuming it is bonded to the neighbours installation as well).
What would you do?
What would you do?