US President Joe Biden reiterated his concerns to German Chancellor Angela Merkel on Thursday about the nearly completed Nord Stream 2 project, a pipeline that will deliver gas directly from Russia to Germany.
According to the US, the gas pipeline will increase Europe's dependence on Russian gas.
That would allow Russia to exert political pressure on vulnerable Eastern and Central European countries, including US ally Ukraine.
Biden was pressured by Republicans to raise the issue just before meeting Merkel at the White House.
Republican Senator Marco Rubio, for example, wrote a public letter to Biden in which he stated that the pipeline is already having an economic impact on Ukraine.
According to Rubio, Gazprom, the Russian energy company that operates Nord Stream 2, has "already begun to reduce the use of pipelines in Ukraine".
As a result, Ukraine would miss out on valuable transit fees.
US: 'Russia should not use energy as a weapon'
Biden and Merkel, however, showed unity in their attitude towards Russia.
Biden said at a joint press conference: "While I have reiterated my concerns about Nord Stream 2, Chancellor Merkel and I absolutely agree that Russia should not use energy as a weapon to force or threaten its neighbors. ."
Merkel said during the same press conference that Ukraine must remain an "energy transit country" even after Nord Stream 2 goes live.
Biden emphasized that the difference of opinion between the German and American allies does not disturb the mutual relations.
"Good friends should be able to disagree."