The close-doors meeting at the Foreign Ministry's guesthouse Villa Borsig brings together Germany's Frank-Walter Steinmeier, Russia's Sergei Lavrov, France's Laurent Fabius and Ukraine's Pavlo Klimkin to continue the search for solutions to the ongoing Ukrainian crisis.
The "Normandy format" dates back to June 2014, when the leaders of Russia, Germany, France and Ukraine met during celebrations of the 70th anniversary of the allies' Normandy landing in France to lay down a roadmap for a sustainable ceasefire in eastern Ukraine.
The senior diplomats have gathered in Berlin to discuss the implementation of the Minsk peace plan, agreed in Belarus in September 2014, and confirm the upcoming Normandy quartet summit talks on Ukraine, due to be held in Kazakhstan's capital Astana on January 15 and 16.
The Minsk format talks, which allow representatives of the self-proclaimed Donetsk and Luhansk people's republics to participate, have resulted in the implementation of a ceasefire between the Ukrainian army and independence supporters.
Both sides, however, have subsequently accused each other of violating the truce.