Originally posted by the Voice of America. Voice of America content is produced by the Voice of America, a United States federal government-sponsored entity, and is in the public domain. Pompeo Departs for Germany to Boost Transatlantic Ties Nike Ching WASHINGTON - The United States is warning a key European ally on growing threats from Russia, as Germany gears up to mark the 30th anniversary of the fall of the Berlin Wall. Secretary of State Mike Pompeo departed for Germany early Wednesday, for a trip marking three decades since the demolition of the wall and to underscore what U.S. officials say is the need for continuing a strengthened transatlantic partnership. The top U.S. diplomat's meetings with leaders in Germany also come days after Denmark cleared one of the last legal hurdles to a proposed natural gas pipeline connecting Russia and Germany, known as Nord Stream 2. A senior State Department official said the U.S. is concerned about the "energy security" for European partners, calling Nord Stream 2 "primarily a political tool" of Russia and "not a purely commercial project." "Our concerns have been regularly expressed. We see this as a tool through which Russia seeks to use energy to advance Russia's geopolitical agenda," the official told VOA on Tuesday during a background briefing. That official added Nord Stream 2 "jeopardizes" the priority of energy security by "making European countries and our allies more reliant on single country sources of energy." .