The Organization for Security and Cooperation in Europe (OSCE) plans to double to 500 the number of observers stationed in Ukraine in January, spokesman Michael Bociurkiw told dpa on Sunday. Previously, 250 observers from OSCE's Special Monitoring Mission to Ukraine were engaged in inspecting the fighting between government forces and pro-Russian separatists in the east of the country. The situation in the embattled east had become calmer, Bociurkiw said, but there were reports of violations of an agreed ceasefire between the two sides. "One of the cornerstones of the Minsk agreement, namely the withdrawal of heavy weaponry, has not been implemented to any appreciable degree," he said. The Ukraine government and the insurgents came to an agreement in the Belarusian capital but have so far failed to carry it out, with both sides continuing to attack each other through the weekend. No date has yet been set for a continuation of the Minsk talks.