Entry into force of tax treaty: diplomatic notifications trigger commencement; India and Saudi Arabia apply tax effects to subsequent periods. Entry into force requires reciprocal written notification through diplomatic channels; the Convention takes effect on the first day of the second month following the month in which the later notification is received. The Convention applies in India to income for fiscal years beginning on or after the first fiscal year starting in April following the calendar year of entry into force. In Saudi Arabia it applies to taxes withheld at source for amounts paid or credited on or after the January period following that calendar year and to other taxes for taxable years beginning on or after that January period.