MOSCOW — In another apparent tit for tat provoked by the Magnitsky Act, Russia on Wednesday said it was withdrawing from an agreement that provided help from the United States in fighting narcotics and human trafficking and improving the rule of law.

The decision was announced on a government website, in a statement from Prime Minister Dmitry Medvedev. His order canceled a 2002 agreement that also was meant to improve enforcement of intellectual property rights. In his statement, Medvedev said the agreement ‘‘does not address current realities.’’