Related Rule
New Zealand
Practice Relating to Rule 62. Improper Use of Flags or Military Emblems, Insignia or Uniforms of the Adversary
New Zealand’s Military Manual (1992) states: “It is prohibited to make use of the flags or military emblems, insignia or uniforms of adverse Parties while engaging in attacks or in order to shield, favour, protect or impede military operations.” 
New Zealand, Interim Law of Armed Conflict Manual, DM 112, New Zealand Defence Force, Headquarters, Directorate of Legal Services, Wellington, November 1992, § 502(8).
In respect of naval warfare, the manual provides:
According to custom, it is permissible for a belligerent warship to use false colours and to disguise her outward appearance in other ways in order to deceive an enemy, provided that prior to going into action the warship shows her true colours. Aircraft are not, however, enentitled to use false markings. 
New Zealand, Interim Law of Armed Conflict Manual, DM 112, New Zealand Defence Force, Headquarters, Directorate of Legal Services, Wellington, November 1992, § 713(1); see also § 713(3).
The manual also specifies: “The use of false markings on military aircraft such as the markings of … enemy aircraft is the prime example of perfidious conduct in air warfare and is prohibited.” 
New Zealand, Interim Law of Armed Conflict Manual, DM 112, New Zealand Defence Force, Headquarters, Directorate of Legal Services, Wellington, November 1992, § 611(2).
The manual further states that “improperly using … the national flag or military insignia and uniform of the enemy” is a war crime. 
New Zealand, Interim Law of Armed Conflict Manual, DM 112, New Zealand Defence Force, Headquarters, Directorate of Legal Services, Wellington, November 1992, § 1704(2)(f).
Under New Zealand’s International Crimes and ICC Act (2000), war crimes include the crimes defined in Article 8(2)(b)(vii) of the 1998 ICC Statute. 
New Zealand, International Crimes and ICC Act, 2000, Section 11(2).