"It must be condemned . . . supplying this kind of equipment facilitates the aggression of the Russian military," Foreign Minister Grzegorz Schetyna told PAP news agency of the €85-million ($91 million sale).
The netting is designed to escap e detection by radar and infra-red captors and constitutes the largest ever sale of Swiss military equipment to a Russian company.
The contract was signed in August 2014, before Bern decided to mirror EU sanctions against Russia, Swiss economic policy spokesman Fabian Maienfisch told the ATS news agency on Sunday.
Maienfisch declined to name either the civilian Russian buyer or the Swiss supplier.
The United States and the European Union imposed a first round of sanctions against Moscow in March 2014 over its actions in Ukraine, followed by further penalties as the conflict has dragged on.