But critics of this argument pointed out that the US also wants to boost sales of liquefied natural gas (LNG) to Europe. US sanctions on Russian vessels laying the pipeline succeeded in delaying Nord Stream 2, angering Germany. But Biden, eager to rebuild transatlantic ties that were badly strained by Trump, unexpectedly waived sanctions in May on the Russian-controlled company behind the project. Analysts saw the move as an olive branch to Berlin, whose support Washington is counting on in the face of other challenges, including a rising China. Zelensky said the sanctions waiver was a win for Russian President Vladimir Putin. Reaffirming support for Ukraine, Biden hosted Zelensky at the White House in early September. After the meeting Zelensky told reporters Biden had assured him the United States would impose sanctions on the pipeline if there were "violations" from Russia that would create problems for Ukraine's energy security.