A European Commission proposal to extend the bloc’s internal energy market rules to regulate Russia’s planned Nord Stream 2 gas pipeline to Germany has been rejected. An EU legal opinion warned the pipeline could undercut efforts to reduce dependence on Moscow and its support for Kiev.

Seen by the Reuters news agency, the opinion from the legal service of the Council of the European Union, the body where EU ministers meet, said applying EU rules to offshore pipelines may breach UN law regulating the seas.

Last year, the Commission proposed changes to its gas directive to make all import pipelines subject to rules that require they not be owned directly by gas suppliers, apply non-discriminatory tariffs and make capacity available to third parties.

The Nord Stream 2 project, fully owned by Russia’s gas export monopoly Gazprom, is far from complying with the so-called third energy package rules.

“The Union does not have jurisdiction to apply energy law… which is unrelated to the economic exploitation of the EEZ, to pipelines crossing the EEZ of Member States,” the Council’s legal service said.

According to Reuters, the Commission’s moves to regulate Nord Stream 2, including by seeking a mandate from member states to negotiate directly with the Russian government, challenges big member states, which have companies invested in the project.

Five European energy firms are financing the 1,225km pipeline to carry 55bn cubic meters of gas per year: German energy groups Uniper and Wintershall, Anglo-Dutch group Shell, Austria’s OMV and France’s Engie.