Ukrainian President Petro Poroshenko plans to travel to Berlin in the second half of Monday, August 24, to take part in trilateral negotiations with French President Francois Hollande and German Chancellor Angela Merkel, a Ukrainian diplomatic source told Interfax.

"Following all events related to the celebration of Independence Day in Ukraine, the president will depart for negotiations in Berlin in the second half of the day," the source said on Tuesday evening.

Poroshenko, Hollande, and Merkel will discuss ways to de-escalate the conflict in Donbas and the increasing intensity of the shelling of Ukrainian government forces' positions and populated areas controlled by Kyiv by the militia, the sources aid.

The negotiations will be arranged at the Ukrainian president's initiative, he said.

French media reported earlier on Tuesday that Hollande, Merkel and Poroshenko planned to meet in Berlin next Monday to discuss the deterioration of the situation in eastern Ukraine,.

French Foreign Minister Laurent Fabius had earlier expressed his concerns about the developments in eastern Ukraine.