Disagreements remain between the "Normandy format" member countries, German Foreign Minister Frank-Walter Steinmeier said at a meeting with his Russian, French and Ukrainian counterparts in Berlin.

"Our differences of opinion confirm how difficult it is to make progress in the search for a political solution [to the Ukrainian crisis]," the minister said.

At their meeting, the "Normandy format" foreign ministers called for a meeting of the Contact Group (Russia, the Organization for Security and Cooperation in Europe, the Kyiv authorities and representatives of Ukraine's south-eastern regions), Steinmeier said.

"We call on the international Contact Group to hold a new meeting in order to help the implementation of the Minsk agreements on Ukraine to get underway," he said.

The "Normandy format" foreign ministers are expected to meet again next meet, he said.

However, a condition for holding such a meeting should become progress in settling the Ukrainian conflict, the German minister said.

The four countries' political directors will meet ahead of the ministerial meeting, he said.

"We have agreed that if progress is achieved at the level of political directors in the coming days, we will be ready to hold another meeting next week in order to continue our current discussions," Steinmeier said.