In a new enforcement effort that started on July 1, German authorities have begun stopping tankers passing through the country’s waters to check whether they carry valid insurance for oil spill damage.

According to the German Federal Foreign Office, the measure is one of a range of initiatives spearheaded by the European Union (EU) to push back against the Russian so-called ‘shadow’ (or ‘dark’) fleet as well as to improve the security of maritime transport and help preserve the marine environment.