Section 115(7) in The Naval Ceremonial, Conditions Of Service And Miscellaneous Regulations, 1964
(7)Indian Naval Ships approaching or leaving an anchorage where ships of any other country are wearing a foreign national flag at half-mast at the main, or have their colours at half-mast, shall, while within sight of the ships in port, hoist or keep the foreign national flag at half-mast or half-mast their own colours.
