German Foreign Minister Heiko Maas made the plea after a meeting with his Ukrainian counterpart, Pavlo Klimkin, in Ukraine’s capital city of Kiev on Friday.
"We would like all sides involved in the conflict in the east and in the Azov Sea to contribute to the de-escalation of the conflict. That is why it is essential to use all diplomatic means as we want to prevent outbreak of another conflict," Maas said.
"We are concerned about the situation in the Azov Sea…The crisis of November 2018 should not repeat again. And for that reason, we need clear information about what is going on in the region," he added.
The top German diplomat also called on Russia to ensure "permanent" freedom of passage through the Kerch Strait off the coast of Crimea, which rejoined Russia in a 2014 referendum.
The Sea of Azov is a strategic ocean route linked to the Black Sea by the narrow Strait of Kerch where Russia has built a bridge to link the Crimean Peninsula with the mainland.
In November, Russia’s naval forces intercepted and seized three Ukrainian vessels along with their crew after they illegally entered Russian waters off the coast of Crimea in the Sea of Azov. The Kremlin said the seizure of the ships was lawful because they were trespassing on Russia’s territorial waters off the coast of Crimea.
Kiev and its Western allies, however, have been trying to portray the incident as an instance of what they call Russian “aggression.”
The tense situation in the Sea of Azov came against the backdrop of a protracted armed conflict between Kiev troops and pro-Russia forces in eastern Ukraine.
The armed conflict broke out following the overthrow of Ukraine's former pro-Russia president, Viktor Yanukovych, in February 2014, and intensified after people in Crimea voted for reunification with the Russian Federation in March 2014.
The West brands the reunification as "annexation" of the territory by Russia, a charge that Moscow has vehemently denied.
Armed confrontation between the pro-Russia forces and the Ukrainian military has killed more than 10,000 people, according to the United Nations.
The deadly conflict has also led a US-led coalition Western countries, including Germany, to impose a series of economic sanctions against Moscow.