The protocol requires that ratifying governments ensure that while their armed forces can accept volunteers below the age of 18, they can not be conscripted and "States Parties shall take all feasible measures to ensure that members of their armed forces who have not attained the age of 18 years do not take a direct part in hostilities".
ICRC commentary
The sentence "States Parties shall take all feasible measures to ensure that members of their armed forces who have not attained the age of 18 years do not take a direct part in hostilities" was adapted from Article 77.2 of the Additional Protocol I to the Geneva Conventions of 12 August 1949, and relating to the Protection of Victims of International Armed Conflicts, adopted in 1977, with an alteration from fifteen years to eighteen years and some... Read More