Ukrainian President Volodymyr Zelensky also joined the German-Ukrainian municipal partnership conference in the eastern German city of Leipzig on Wednesday.
He emphasised that it was not only Ukraine that was under threat from the Russian regime, neighbouring countries were also in danger.
Cities in Germany and Ukraine have a European attitude towards people, Zelensky said, adding this relationship protects human lives.
“It is very important that we don’t just use the instruments that the state has,” the Ukrainian leader said.
Leipzig, which is hosting the conference, has had a twin-city relationship with the Ukrainian capital Kiev for 62 years.
Steinmeier’s office said it is the oldest German-Ukrainian city partnership.
Kiev’s mayor, former professional boxer Vitali Klitschko, was also a guest at the conference. German support is vital for Ukraine, said the 52-year-old.
“Together we are much stronger.”
Ukraine is also fighting for democratic values and its democratic future, said Klitschko.
Development Minister Svenja Schulze emphasised in a welcoming address that the commitment shown by towns and communities is still overwhelming.
“Local authorities will play a decisive role in the reconstruction of Ukraine,” said the SPD politician.
Germany will continue to help as long as it is necessary, she added.