The King told Ukrainian refugees “I'm praying for you” as he visited a centre for new arrivals in Germany during the second day of his state visit.
Charles met families who escaped to Germany after he praised the nation's “courageous, important and appreciated” decision to send “significant” military support to Ukraine in a historic address to the Bundestag.
At Berlin's old Tegel Airport the King met recently arrived Ukrainians, a few of more than a million who have sought refuge in the country, and in a lighter moment played table football with some of the group.
On several occasions Charles clasped his hands together and told refugees “I'm praying for you”.
The King earlier made history by delivering the first speech by a British monarch during a session of the Bundestag.
He told the packed chamber: “The unprovoked invasion of Ukraine has inflicted the most unimaginable suffering on so many innocent people.
“Countless lives have been destroyed; freedom and human dignity have been trampled in the most brutal way. The security of Europe has been threatened, together with our democratic values.
King Charles and Berlin's Mayor Franziska Giffey visit the arrival and temporary accommodation centre for Ukrainian refugees
“The world has watched in horror - but we have not stood by. Even as we abhor the appalling scenes of destruction, we can take heart from our unity - in defence of Ukraine, of peace and freedom.
“Germany and the United Kingdom have shown vital leadership. As Europe's two largest donors to Ukraine, we have responded with taking decisions which might previously have seemed unimaginable. Germany's decision to send such significant military support to Ukraine is remarkably courageous, important and appreciated.”
Charles and Camilla visit a food market on Wittenbergplatz in Berlin
Charles was given a tour of the Ukraine Arrival Centre by German President Frank-Walter Steinmeier and stopping to speak to families registering after just arriving, asked: “Was it very difficult to get out of Ukraine? Are you pleased to be here?”
Charles, who is midway through a state visit to Germany with the Queen Consort, took up the offer of a game of table football in the refugee centre's games room and joked: "I remember trying this when I was younger.”
The Queen Consort and First Lady Elke Budenbender meet opera singers from the Komische Opera Berlin
The Queen Consort and First Lady Elke Budenbender wave outside the Komische Opera Berlin