Treaty termination provision allows either State to end the tax convention with prior diplomatic notice, altering tax applicability. The Convention establishes a termination mechanism allowing either Contracting State to terminate by diplomatic notice after a ten-year period, causing cessation of treaty effects for defined taxes from specified taxable periods following notice. It clarifies that construction and building-site duration tests exclude time on unrelated sites, apply separately to unconnected sites or groups of connected sites, and treat a commercially and geographically coherent building site as a single site; that permanent establishment activity is assessed on all relevant circumstances notwithstanding contracting through head office; and that interest from direct operation receipts of international aircraft is included in profits while reinvested interest is excluded.