Former President of the European Council Donald Tusk called the decision to build the Nord Stream 2 pipeline the biggest mistake of outgoing German Chancellor Angela Merkel, during a conference on Sunday.

"From the perspective of EU interests, Nord Stream 2 is a bad project," Tusk said, as reported by Polish news outlet PAP.

Tusk also stated that Merkel had recognized this in a conversation the two had had. He added that Merkel had been 'helpless' in the face of the lobbying of German business interests.

"I've done everything I could to make the EU less reliant on Russian gas, including establishing an energy union," said Tusk.

Who is against the Nord Stream 2 pipeline?

Nord Stream 2 is a gas pipeline from Russia to Germany, running through the Baltic Sea. It bypasses Poland, Belarus, Ukraine and the Baltic states.

Ukrainian President Volodymyr Zelenskyy has been vocal in his opposition to the pipeline, calling it a "dangerous geopolitical weapon of the Kremlin". By bypassing Ukraine, the pipeline deprives the country of gas transit fees.

Poland has been one of the most vocal critics of the pipeline, arguing that it hands Moscow influence over Central and Eastern European countries. Tusk has previously voiced open criticism of Merkel over the project.

According to Tusk, the Netherlands, Austria and Hungary were in favor of the project, whereas the Czech Republic expressed neutrality.

What is the US position on Nord Stream 2?

The US has long objected to the pipeline, but the Biden administration waived sanctions as part of a compromise with Germany. In this deal, Germany and the United States agreed to invest in green energy in Ukraine and to impose sanctions on Russia if it were to use the pipeline as a political weapon.

Last week, the US imposed sanctions on a Russian-linked shipping company for its role in the project. These sanctions did not target the main company finishing the project.

On Sunday, the German government urged the US Congress not to sanction the pipeline, arguing that this would "ultimately damage transatlantic unity," according to a report by US news outlet Axios based on classified documents.

In the documents, Germany argues that the pipeline presents "no threat to Ukraine as long as reasonable gas transit is ensured." It says any potential sanctions would be "a victory for (Russian President Vladimir) Putin" because it would damage transatlantic unity.

Ukraine has openly called on US lawmakers to sanction the project, arguing it presents an existential threat.

Who is Donald Tusk?

Donald Tusk was Prime Minister of Poland from 2007 to 2014 and President of the European Council from 2014 to 2019. He founded the Civic Platform (PO), which is currently the largest opposition party in the Polish parliament. Tusk has been the President of the European People's Party (EPP) since December 2019.

Tusk vowed to fight "populists, manipulators and autocrats" during a speech after being elected President of the EPP. Tusk is a fierce opponent of Poland's ruling Law and Justice party (PiS): in a Civic Platform party congress in July, he declared "evil reigns in Poland and we want to fight it".

Edited by Alistair Walsh