Related Rule
United States of America
Practice Relating to Rule 145. Reprisals
Section E. Termination of reprisals as soon as the adversary complies again with the law
The US Naval Handbook (1995) states: “To be valid, a reprisal action must conform to the following criteria: … 7. A reprisal action must cease as soon as the enemy is induced to desist from its unlawful activities and to comply with the law of armed conflict.” 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-2.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Transportation, US Coast Guard, October 1995 (formerly NWP 9 (Rev. A)/FMFM 1-10, October 1989), § 6.2.3.1.
The Annotated Supplement to the US Naval Handbook (1997), with reference to the rule that a reprisal must cease as soon as the enemy is induced to desist from its unlawful activities, states:
When, for example, one party to an armed conflict commits a breach of law but follows that violation with an expression of regret and promise that it will not be repeated, then any action taken by another party to “right” the situation cannot be justified as a lawful reprisal. 
United States, Annotated Supplement to the Commander’s Handbook on the Law of Naval Operations, prepared by the Oceans Law and Policy Department, Center for Naval Warfare Studies, Naval War College, Newport, Rhode Island, November 1997, § 6.2.3.1, footnote 44.
The US Naval Handbook (2007) states: “To be valid, a reprisal action must conform to the following criteria: … 7. A reprisal action must cease as soon as the enemy is induced to stop its unlawful activities and to comply with the law of armed conflict.” 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-12.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Homeland Security, US Coast Guard, July 2007, § 6.2.4.1.