WASHINGTON — President Biden will meet with Olaf Scholz, the new chancellor of Germany, at the White House on Monday, a visit designed to publicly shore up a key link in the Western alliance amid concerns that Germany has not been a forceful enough partner in calming tensions between Russia and Ukraine.

It has been a rocky first few months on the job for Mr. Scholz, who took over from Angela Merkel, a politician who had worked with four U.S. presidents. Berlin’s reluctance to join its NATO allies in outlining consequences for Russia if it invades Ukraine has damaged Mr. Scholz’s reputation to the point that last week his ambassador in Washington sent a warning home: Many in the United States, she wrote, see Germany as an “unreliable partner.”

The situation represents a diplomatic pivot for Mr. Biden, who extolled his relationship with Ms. Merkel in a meeting at the White House in July: “Good friends can disagree” on matters including how each conducted relations with Russia, he said at the time. More than six months later, Mr. Biden does not have the luxury of agreeing to disagree about Russia: Biden administration officials believe that the Russian military has already assembled 70 percent of the forces it would need to mount a full-scale invasion of Ukraine.

In a call with reporters on Sunday, administration officials said that Mr. Biden would be looking to discuss a package of “swift and severe” sanctions against Russia if its president, Vladimir V. Putin, decides to invade Ukraine. In recent weeks, Mr. Biden has threatened severe economic sanctions on Russia’s financial sector and against members of Mr. Putin’s inner circle.

Mr. Scholz has been less willing to publicly outline any such consequences, a low-key stance that has drawn criticism from both Republicans and Democrats: “The Germans are right now missing in action,” Senator Richard Blumenthal, Democrat of Connecticut, who visited Ukraine in January, said recently. Senator Rob Portman, Republican of Ohio, has publicly criticized Germany for not allowing flights carrying military aid for Ukraine to fly through German airspace.

Mr. Biden and Mr. Scholz are also likely to discuss the contentious $11 billion Nord Stream 2 pipeline, a natural gas conduit being built between Germany and Russia. The pipeline has been assailed by Mr. Biden and his advisers as little more than a coercive tool against Ukraine and other allies, even though the president agreed last year to waive sanctions related to the project.

The pipeline is currently on hold as European Commission officials investigate whether the project, designed by Gazprom, Russia’s most prominent energy company, is in compliance with European energy policy. There are growing calls among U.S. lawmakers to shut down the pipeline if Russia mounts an invasion into Ukraine. A senior official in the Biden administration told reporters on Sunday night that if Russia did invade, the project would not move forward.

Mr. Scholz has been vague about whether he would agree to terminate the pipeline project. But he told The Washington Post, in an interview published on Sunday evening, that Germany’s response with its allies to such an invasion would be “united and decisive.”

Mr. Biden and Mr. Scholz will hold a news conference on Monday afternoon after their meeting.