The spokesman did not provide details on the visit, which started a day after Russian strikes on Ukraine's northeastern city of Kharkiv killed three people and wounded 60 others.

This was Pistorius's first trip to Ukraine since German Chancellor Friedrich Merz took office. Pistorius last visited Ukraine in January.

On Tuesday, Merz slammed Russian "terror against the civilian population" in Ukraine after Moscow escalated its bombardments.

He said Russia's latest actions were "anything but a proportionate response to the very precise Ukrainian attacks on military airfields and infrastructure in the last week".

Merz's comments come ahead of a G7 summit in Canada on June 15-17 and a NATO meeting later in the month, where allies will push US President Donald Trump to be more aggressive in punishing the Kremlin.