European Council President Antonio Costa, EU foreign policy chief Kaja Kallas and European Commissioner for Enlargement Marta Kos arrived in Ukrainian capital Kyiv on Sunday in a symbolic show of support for Ukraine on their first day in office. 

"From day one of the war, the EU has stood by the side of Ukraine. From day one of our mandate, we are reaffirming our unwavering support to the Ukrainian people," Costa wrote on X. 

(With input from agencies)