This weekend, Vice President Kamala Harris will face her most important foreign policy assignment yet in Germany, where she will try to keep European allies united amid growing concern about a Russian invasion of Ukraine.

She will attend the annual Munich Security Conference as President Joe Biden and other Western leaders warn that the threat of an invasion remains high, despite Russian President Vladimir Putin’s statements to the contrary.

The Kremlin has made unsubstantiated claims that some of the estimated 150,000 Russian forces encircling Ukraine have been withdrawn to their bases. Officials at the White House disagree, claiming that intelligence shows Russia has added 7,000 more troops near Ukraine in recent days and has increased preparations for potential false flag operations that could be used as a pretext to start a war.

On the sidelines of the Munich conference, Harris will meet NATO Secretary-General Jens Stoltenberg and hold a multilateral meeting with the leaders of Latvia, Lithuania, and Estonia. She is set to deliver a major speech on the administration’s efforts to counter Russian aggression on Saturday. She is scheduled to meet with Ukrainian President Volodymyr Zelenskyy and German Chancellor Olaf Scholz following her speech.

According to White House press secretary Jen Psaki, Harris will “reiterate to the rest of the world our ironclad commitment to our NATO allies, our commitment to defending Ukraine’s territorial integrity and sovereignty, and our commitment to imposing severe economic consequences should Russia invade.”

In recent years, both US and Russian leaders have used the Munich gathering to deliver messages to a who’s who of transatlantic leaders.

In 2019, then-Vice President Mike Pence made a forceful case for President Donald Trump’s “America First” worldview, drawing a lukewarm response from the mostly European audience. Hours later, as a private citizen and not yet a 2020 presidential candidate, Biden assured European allies that “this too shall pass” and “America will be back.”

In 2007, Putin used his appearance in Munich to launch a broadside against NATO, accusing the alliance of stationing “frontline forces on our borders.” Last year’s conference, which was held virtually due to the coronavirus pandemic, saw new President Biden declare “America’s back” in an address that addressed economic and security concerns raised by adversaries Russia and China.

Harris is traveling to Munich at a time when the Biden administration is attempting to persuade Moscow to de-escalate the biggest security crisis between Russia and the West since the Cold War.

Throughout the crisis, the Biden administration’s public-facing efforts have been largely entrusted to the president’s national security adviser Jake Sullivan and Secretary of State Antony Blinken, both of whom will be in attendance.

According to a senior administration official who briefed reporters ahead of Harris’ trip, Harris has been a constant presence by Biden’s side throughout the crisis. Most mornings, the vice president joins Biden in the Oval Office for the presidential daily briefing. She’s also been a constant presence in White House strategy sessions about countering Russia, according to the source.

After a rocky first year as vice president, Harris will have an opportunity to show off her foreign policy skills in Munich. Her portfolio includes tackling a slew of difficult policy issues with no clear solution or immediate payoff. Among the difficult tasks she faces are leading the administration’s push for a voting rights bill and addressing the underlying causes of migration to the United States’ southern border.

The conference, which starts on Friday, will be Harris’ fifth overseas trip as vice president. She has previously traveled to Guatemala and Mexico, Singapore and Vietnam, France, and, most recently, Honduras.

The Munich conference, according to Matt Bennett, executive vice president of the center-left think tank Third Way and a former aide to Vice President Al Gore in the Clinton White House, provides the kind of backdrop where Harris, a former prosecutor, can stand out.

“She was at her best in the Senate when she was litigating her case against an adversary,” Bennett said. “These are the occasions for which she was created.”