Related Rule
Practice Relating to Rule 22. The Principle of Precautions against the Effects of Attacks
Section B. Feasibility of precautions against the effects of attacks
At the CDDH, Italy stated:
The words “to the maximum extent feasible” at the beginning of [Article 58 of the 1977 Additional Protocol I], however, clearly show the real aim of this rule: this is not a question of absolute obligations, but, on the contrary, of precepts that should be followed if, and to the extent that, the particular circumstances permit. 
Italy, Statement at the CDDH, Official Records, Vol. VI, CDDH/SR.42, 27 May 1977, p. 232.
Upon ratification of the 1977 Additional Protocol I, Italy declared: “The word ‘feasible’ means that which is practicable or practically possible, taking into account all circumstances ruling at the time, including humanitarian and military considerations.” 
Italy, Declarations made upon ratification of the 1977 Additional Protocol I, 27 February 1986, § 2.