President Joe Biden began his first overseas trip as president on Wednesday, seeking to reaffirm the United States’ standing on the world stage with familiar allies and portraying himself as the leader of the free world, including his first face-to-face meeting with Russian President Vladimir Putin.

After landing at Royal Air Force Base Mildenhall in the United Kingdom, Biden delivered a fiery speech to American service members stationed there, telling them he was going to Geneva “to meet with Mister Putin to let him know what I want him to know.”

It was Biden’s first stop on his trip to Europe, and he laid out many of his trip’s major themes: America’s return to the world stage, reaffirming support for NATO, and celebrating multilateralism to address the world’s most pressing challenges, from the pandemic to global warming, from Russia to China.

His solemn demeanor contrasted with a lighthearted exchange with reporters before boarding Air Force One in Maryland. “Beware of cicadas,” Biden warned them, explaining that he had to brush one off his neck. “I only got one, and it got me.”

His trip was previewed by the White House on Tuesday. The trip’s high point will be his first meeting as president with Russian President Vladimir Putin next Wednesday in Geneva. There, Biden will have to tread carefully. According to the White House, he intends to issue a strong warning that malicious attacks in the cybersecurity, military, and political spheres will no longer be tolerated, while avoiding any escalation in the already tense relationship and seeking to restore “predictability” and “stability.”

Biden hopes to gain the support of long-term US allies ahead of that summit by attending the G-7 summit in the United Kingdom and a NATO summit in Brussels. Wary after the shock of the Trump era, European allies will look to Biden to reassure them that the political upheaval of the last four years was a blip rather than a true sea change, and that there is substance behind Biden’s catchphrase “America is Back.”

Along the way, Biden will attempt to frame everything in a way that is appealing to Americans at home. He’ll discuss a wide range of issues with world leaders, from climate change to taxes, defense to trade, and work to persuade Americans that it’s all in the service of his “Build Back Better” agenda, which aims to recover equitably from the pandemic’s economic downturn Biden, who has grown accustomed to updated Centers for Disease Control and Prevention guidance allowing fully vaccinated Americans to go maskless in most settings, will be forced to return to strict requirements at the G-7. Fears of a third COVID-19 outbreak are circulating in the United Kingdom, where vaccine distribution has lagged.

Meeting demands from allies and partners to share COVID-19 vaccines will be a significant challenge for Biden. The United States has committed to distributing 80 million doses around the world by the end of June, with 25 million doses already assigned to destinations. The United States’ commitment to share 80 million doses is five times greater than any other country’s thus far, but it is far from sufficient to meet global demand.

During the most recent G-7 virtual meeting in April, leaders refused to commit to sharing a specific number of doses or provide a timeline. A group of think tanks and public health experts called on G-7 leaders on Monday to commit to sharing 1 billion to 2 billion doses by the end of 2021 in order to facilitate widespread global vaccination by the end of 2022.

Following four years of former President Donald Trump representing the United States on the world stage, Biden will make his first trip as president. Unlike Trump, who frequently disrupted the status quo at NATO gatherings and criticized the organization as “obsolete,” Biden is expected to take a more traditional approach.

In his op-ed, Biden vowed to “reiterate the United States’ unwavering commitment to Article 5 and to ensuring our alliance remains strong in the face of every challenge, including cyberattacks on our critical infrastructure.”

Biden will also be the 12th president of the United States to meet with Queen Elizabeth II. The meeting comes at a critical juncture in the Queen’s life, following the death of Prince Philip and the birth of a granddaughter.