"We are exerting as much persuasive power as we possibly can" to stop the project through diplomatic means first, she said, but she noted that Congress has given the government authority to impose sanctions on such Russian pipeline projects if necessary.
The German government's point man for Russia, Dirk Wiese, said it would continue to look for "islands of cooperation" with Russia, including a continued commitment to the Iranian nuclear accord, despite differences over Ukraine and European Union sanctions.
The United States is opposed to the Nord Stream 2 natural gas pipeline project because it would increase Moscow's influence in Europe.
In early April, after meeting with the leaders of Latvia, Lithuania and Estonia at the White House, Trump criticized the Nord Stream 2 pipeline.
November 12, 2017 the head of the European Council, Donald Tusk urged the EU to accelerate work on the legislative block of the Russian project Nord stream-2.
Sandra Oudkirk, US Deputy Assistant Secretary of State for Energy Diplomacy, told reporters in Berlin that Washington viewed the pipeline project as a bad choice, adding the US was skeptical whether Russian transit guarantees for other countries such as Ukraine were enforceable.
German Chancellor Angela Merkel said today (10 April) that plans for a controversial second underwater pipeline to bring gas from Russian Federation could not go forward without Ukrainian involvement in overland transit.
Trump told Chancellor Angela Merkel last month that Berlin should drop support for the pipeline linking Russian Federation and Germany if it wants to avoid a trans-Atlantic trade war, according to a report by The Wall Street Journal, which cited U.S., German and European officials.
"The new project would permit new technologies to be placed along the pipeline route, and that is a threat", she said.
Altmaier has said he is optimistic that a "substantial" amount of gas will continue to flow through Ukraine when the Baltic pipeline starts operating.
Gazprom's Western partners are energy companies Uniper, Wintershall, Engie, Austria's OMV and Anglo-Dutch group Shell.