Greenpeace has taken a stand against President Donald Trump during his visit to Warsaw, Poland’s capital. The president was visiting to attend a joint press conference with Polish president Andrzej Duda, but on Wednesday night, activists drew attention to Trump’s decision to withdraw from the Paris Agreement on climate change by projecting a message onto Poland’s largest building.

The Polish and German branches of Greenpeace worked together to project the words “No Trump Yes Paris” and “Planet Earth First” onto the sides of the Palace of Culture and Science, one of the tallest buildings in Europe at 778 feet. As Trump arrived ahead of his press conference the following morning, Warsaw’s iconic landmark was emblazoned with a message for the president combatting his anti-climate change stance.

“Withdrawing from the Paris Climate Agreement would turn America from a global climate leader into a global climate deadbeat,” Greenpeace USA Executive Director Annie Leonard said in a previous statement. “Global climate action is not a legal or political debate, it’s a moral obligation to protect our planet and people.”

The Palace of Culture and Science on Wednesday. Greenpeace

Warsaw is Trump’s first stop on a European tour that will also see him visit Hamburg in Germany for the G20 summit. There, he will meet Russian president Vladimir Putin for the first time, along with numerous other leaders. Greenpeace’s protest comes at the start of what could be one of the most contentious G20 summits in history.

The Palace of Culture and Science on Wednesday. Greenpeace

The G20 group is comprised of the United States, Germany, France, Canada, Russia, Argentina, Australia, Brazil, India, Indonesia, Italy, Japan, Mexico, Saudi Arabia, South Korea, Turkey, the U.K., China, and South Africa. Brazilian President Michel Temer and Saudi King Salman bin Abdulaziz Al Saud will not be attending, although finance minister Mohammed al-Dschadan will be representing Saudi Arabia in the king’s absence.

Trump is expected to clash with leaders at the summit over his climate change stance, in particular with French president Emmanuel Macron and German chancellor Angela Merkel. The pair have already criticized Trump for his decision to withdraw from the Paris Agreement.

Trump is also likely to face further protests in Hamburg during his trip. During Trump’s previous Brussels trip, around 9,000 protesters arrived during the NATO summit. Police are prepared for over 100,000 people to protest during Trump’s Hamburg visit.