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The protest was transmitted orally to the U.S. State Department on Wednesday during a videoconference organized by the Delegation of the European Union to the United States, German government officials told industry representatives at a briefing in Berlin on Thursday, according to two people who attended the meeting, POLITICO reported.

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The statement protested U.S. extraterritorial sanctions in general but the recent sanctions threats against Nord Stream 2 were brought up during the call, officials told the meeting.

A European diplomat confirmed that Wednesday's diplomatic move was based on a statement by the EU's foreign policy chief Josep Borrell in July, in which Borrell said he was "deeply concerned at the growing use of sanctions, or the threat of sanctions, by the United States against European companies and interests."

Nabila Massrali, a spokesperson for the European External Action Service, confirmed the EU "conducted outreach to the U.S. administration" on Wednesday to "reiterate its concerns at the growing use of sanctions, or the threat of sanctions, by the United States against European companies and interests," but insisted it "was not a formal démarche."

The initiative for a coordinated response began three weeks ago among a small number of countries, but in the past two weeks all but three EU countries signed on to the message, German officials said.

Washington expressed surprise at the number of participating countries, the officials added.

Poland was one of the three holdouts, a deputy spokesperson for the Polish representation to the EU said in an email. The other two countries could not be confirmed at the time of publication, POLITICO said.