Russia's adversaries in central and Eastern Europe are worried President Biden isn't willing to fight hard to stop the Russia-Germany gas pipeline Nord Stream 2 — one of Vladimir Putin's core priorities.

Why it matters: The fight is the first significant test of whether Biden's tough rhetoric against the Russian leader will be matched by action. Russian opponents fear Biden doesn't want to antagonize Angela Merkel and won't inflict serious costs on the Germans.

The big picture: The completion of Nord Stream 2 would be a huge geopolitical win for Putin and give him substantial new leverage in Europe. Russia has cut off natural gas supplies to Ukraine as retribution in disputes.

• Bypassing Ukraine with a direct pipeline to Germany helps Russia advance its goal of isolating its former client state, now a struggling democracy, from Western Europe.
• Russian gas currently has to pass through Ukraine on its way to Europe.
• The pipeline is more than 90% complete and could be finished by the summer without a major intervention to stop it.

Driving the news: Until now, messages of concern have been conveyed to the Americans privately. But on Monday, a source close to Ukrainian President Volodymyr Zelensky told Axios: "The Ukrainians are a bit disappointed that President Biden did not commit during the Munich [Security] Conference to use every tool in his power to stop Nord Stream 2."

• "But it is not too late," the source close to Zelensky added, "for the U.S. to take decisive action, and the Ukrainians are hopeful the Biden administration will do so."

The comments follow an unusual joint public statement Monday from the Polish and Ukrainian governments.

• The Polish and Ukrainian foreign ministers co-authored an op-ed in Politico Europe urging Biden to follow the lead of the U.S. Congress and do everything in his power to block the pipeline.
• "We call on U.S. President Joe Biden to use all means at his disposal to prevent the project from completion," the ministers wrote.
• State Department spokesperson Ned Price said in a statement: "The Biden administration is committed to using all available tools to counter Russian malign influence and to support transatlantic energy security goals."
• Price added: "We have been clear that companies risk sanctions if they are involved in the Nord Stream 2 project. We continue to examine entities involved in potentially sanctionable activity."

Behind the scenes: On Friday, the State Department submitted a mandatory report to Congress that was supposed to list all the vessels involved in Nord Stream 2 construction, as well as any insurance firms or other companies involved in the pipeline.

• The report didn't name any new companies that would be a target for U.S. sanctions, according to the Wall Street Journal and confirmed to Axios by a source who's read the report, which has not been publicly released.

Sen. Jim Risch of Idaho, the top Republican on the Senate Foreign Relations Committee, condemned the report as weak and incomplete.

• "Maritime tracking information makes it clear that ships not covered in today's report are currently active in supporting Nord Stream 2 construction," Risch said in a statement. He demanded an "immediate explanation" from the Biden administration.
• Sen. Jeanne Shaheen (D-N.H.) also said the Biden administration must do more to stop the pipeline and that she looked forward to being briefed on "additional measures."

Between the lines: America's partners in Eastern and central Europe want Biden to make clear he's willing to do whatever it takes to stop the pipeline from being completed.

• This would include sanctioning the entire construction fleet and signaling a willingness to sanction the German utility companies that would be receiving the Russian energy.
• President Trump even leveled trade threats at Merkel as part of his hardline tactics to stop Nord Stream 2.
• Secretary of State Mike Pompeo also cleared the path for a wider range of sanctions, saying last summer he was sounding "a clear warning to companies aiding and abetting Russia's malign-influence projects it will not be tolerated. ...Get out now, or risk the consequences."
• Construction on Nord Stream 2 halted during the Trump presidency.

While Team Biden has said the pipeline is a "bad deal" and that they want to stop it, the administration done little so far to suggest it's willing to lean into the fight.

• The Russians seem to have taken notice. Major construction on Nord Stream 2 resumed after Biden took office.