Construction work for Nord Stream 2, the planned Russian gas pipeline to Europe, has started in German coastal waters, despite the threat of sanctions from US president Donald Trump and condemnation from across the EU. The contentious pipeline, which will double Russian gas imports to Germany across the Baltic Sea and reduce shipments through Ukraine, has heightened geopolitical tensions between Europe, the US and Russia, souring relations between Berlin and Washington and highlighting the EU’s fractured stance towards Moscow.

Owned by Kremlin-controlled Gazprom, the project is supported by German Chancellor Angela Merkel’s government but opposed by a large group of EU states. Many fear that the pipeline will increase Europe’s energy dependence on Russia and has been engineered as a political weapon to hurt Kiev. President Trump has lambasted the pipeline, claiming it made Germany “a captive to Russia”, while Washington has warned the five European energy companies that are providing financial support to the €9.5bn project that it could face sanctions. The US has promised to increase shipments of its liquid natural gas to Europe as an alternative.

“The implementation of the most important export projects of Gazprom in the European direction continues,” said Alexei Miller, chief executive of the state-controlled gas export monopoly. “Preliminary work is already underway to lay the pipes of the Nord Stream 2 gas pipeline in the territorial waters of Germany in the Lubmin area.” A spokesman for Nord Stream 2 described the construction in German waters as “preparatory”, but confirmed that the current activities included the building of a connection from the landfall site in Lubmin to the offshore pipeline in deeper waters.