The Presidents of Poland, Lithuania, Latvia and Estonia arrived in Kyiv on Wednesday to meet Ukraine’s President Volodymyr Zelenskyy, the Polish leader’s office said.

The four joined a growing number of European politicians to visit the Ukrainian capital since Russian forces were driven away from the country’s north earlier this month.

Heading to Kyiv with a strong message of political support and military assistance, tweeted Lithuanian President Gitanas Nauseda today. The Polish President’s Office confirmed on Twitter that they had arrived in Kyiv.

The meeting will focus on ways to assist civilians and the military in Ukraine, as well as with investigations of war crimes, said a Spokesman for Estonian President Alar Karis.

It comes the day after U.S. President Joe Biden said, Moscow’s military operation of Ukraine amounted to genocide, while President Vladimir Putin promised Russia would rhythmically and calmly continue its operation and achieve its goals.

The four Presidents’ Offices declined to provide details of the visit for security reasons.