German Foreign Minister Frank-Walter Steinmeier said four-way talks on the crisis in eastern Ukraine had been difficult, but they had made progress.
He spoke after meeting with his Ukrainian, Russian and French counterparts in Berlin on Sunday.
Discussions focused on how to alleviate the humanitarian crisis and bring about a ceasefire in the east, he added.
Ukraine’s military has intensified its operation to expel rebels from two key eastern strongholds in recent weeks.
In the latest development, Ukraine said its forces had advanced into the rebel-held city of Luhansk for the first time in months on Sunday.
The national flag was raised over a police station which had for months been under rebel control, Ukrainian Security Council spokesman Andriy Lysenko said.
The military also acknowledged that a Ukrainian fighter jet had been shot down by rebels near the city, adding that the pilot had managed to parachute to safety, BBC informs.
