BERLIN (AP) — The German government has welcomed a deal between Russia and Ukraine to ensure the continued transit of Russian natural gas to Europe.

In a statement, German Chancellor Angela Merkel called the agreement finalized late Monday in Vienna a “good and important signal to guarantee the security of our European gas supply.”

Germany imports about a third of its natural gas from Russia, mostly through the Nord Stream undersea pipeline.

A planned expansion of the pipeline, known as Nord Stream 2, has caused considerable friction between Berlin and Washington. The United States has warned that the new project risks increasing Europe's dependence on Russia gas and recently opened the way for sanctions against companies involved in its construction.

By contrast, the transit of gas through Ukraine is widely seen as vital for the energy security of countries in southern and eastern Europe.