Ukraine's President Petro Poroshenko has urged NATO to deploy warships to the Sea of Azov following a military standoff in the area between Russia and Ukraine.
Poroshenko's remarks, part of a concerted push by Kiev at gaining Western support for more sanctions against Russia.
In a sharp response, Kremlin spokesperson Dmitry Peskov said the comment was "clearly aimed at provoking further tensions" and driven by Poroshenko's "electoral and domestic policy motives".
Asked by Bild whether German warships should be deployed to the Sea of Azov, he said: "Germany is one of our closest allies, and we hope that states within NATO are now willing to deploy naval vessels to the Sea of Azov in order to support Ukraine and to guarantee its safety."
Accusing Russian President Vladimir Putin of wanting "the old Russian empire back", Poroshenko said: "The only language he understands is the unity of the Western world".
"Crimea, Donbass, the whole country. As Russian tsar, as he sees himself, his empire cannot function without Ukraine. He sees us as his colony," he said.
"We cannot accept Russia's aggressive policy. First, it was Crimea, then eastern Ukraine, now he wants the Sea of Azov.
Germany also has to wonder: what will Putin do next if we don't stop him?"