BRUSSELS—U.S. Secretary of State Antony Blinken said on March 23 the Nord Stream 2 pipeline being built from Russia to Germany ran counter to the European Union’s own interests and could undermine Ukraine.

Germany is pushing for the pipeline’s completion, despite sustained U.S. opposition over more than a decade. Speaking on his first visit to NATO, Blinken said he was due to meet his German counterpart, Heiko Maas, to discuss the issue.

“President (Joe) Biden has been very clear, he believes the pipeline is a bad idea, bad for Europe, bad for the United States, ultimately it is in contradiction to the EU’s own security goals,” Blinken said as he met NATO Secretary-General Jens Stoltenberg.

“It has the potential to undermine the interests of Ukraine, Poland and a number of close partners and allies,” Blinken said, saying that a U.S. law required Washington to impose sanctions on companies participating in the Nord Stream 2 project.

Nord Stream 2 will bypass Ukraine, a Western ally, potentially depriving it of valuable transit fees. It will also increase European energy dependency on Russia and compete with shipments of U.S. LNG.

The pipeline is already around 95% built, and could be finished by September, analysts who monitor tracking data say.

The United States fears Russia could use Nord Stream 2 as leverage to weaken EU states by increasing dependency on Moscow.