The US ambassador to Berlin has defended US sanctions against the Nord Stream 2 pipeline designed to supply the EU with Russian gas as “extremely pro-European”, but Berlin condemned the legislation as “interference” in its internal affairs and Moscow threatened to “respond.” Richard Grenell was speaking as Allseas, the Swiss company that is Nord Stream’s main contractor, said it had suspended work on laying the pipeline. Avocal champion of Donald Trump’s policies, Mr Grenell said: “There are 15 countries, plus the European Commission, plus the European Parliament, that have all voiced concern about the project.”

He said he had been “hearing from European diplomats all day today thanking me for taking such action”, adding that the sanctions, which were signed into law by Mr Trump on Friday, were “an extremely pro-European position”. The US was “very pleased” that Allseas had decided to comply with the sanctions, he added.

Nord Stream 2 is a C9.5bn pipeline that would bring natural gas directly from Russia to Germany via the Baltic Sea. Mr Trump has frequently spoken out against the project, saying it would increase Germany’s reliance on Russian gas and so turn Europe’s largest economy into a “captive” of Russia.

The punitive measures threaten a further deterioration in relations between Berlin and Washington, already damaged by Mr Trump’s constant attacks on Germany’s trade surplus and its failure to meet Nato targets on defence spending.

German finance minister Olaf Scholz described the legislation as “serious interference in Germany and Europe’s internal affairs and our own sovereignty”. “We object to them in the strongest terms,” he told the German TV channel ARD.

Such measures were “incomprehensible and improper for friends that are also linked by our common membership ofNato”, he added.

Russian foreign minister Sergei Lavrov on Sunday warned that Russia would respond to the measures with steps that would not also harm the Russian economy, without elaborating.