The Financial Times has access to the letter. The paper reported on Tuesday that Tusk pointed out to the European Commission that Nord Stream 2 was not in Europe's interest.

According to the Times' assessment, Tusk's letter shows once again how opinions differ inside the EU in the matter of Gazprom and gas deliveries from Russia. While the Commission was trying to gain more control, Germany supported Nord Stream 2, and several of the Eastern European EU members were against it.

Tusk apparently stressed in his letter that the construction of the pipeline went against the efforts of the EU and the European Commission to increase energy security in the aftermath of Russian aggression against Ukraine.

Nord Stream 2 was in clear opposition to the aim the EU had taken in terms of its energy policy, Tusk wrote. The pipeline would increase the dependency on Russian deliveries, and strengthen the position of Russian state gas giant Gazprom against the European Commission.

While the European Union wants Russian gas to enter the EU through Ukraine also after the year 2019, when the country's current contract with Gazprom expires, Nord Stream 2 would clearly go against this goal. So far, the project's supporters have rejected EU attempts at gaining political control, arguing that the project was entirely a business matter.

Brussels' course at this point seems to be to make concessions to the opponents of Nord Stream 2, and to change the situation to the effect that the Commission would have a mandate to conclude a contract with Russia that would include rules concerning Nord Stream 2 as well. In his letter, Tusk apparently called on the Commission to make sure that the EU's rules as well as its political aims were reflected in any such agreement.