KIEV (Reuters) - A fresh round of peace talks involving Russia, Ukraine and the Organization for Security and Cooperation in Europe will be held in the Belarussian capital on Dec. 24 and 26, Ukrainian President Petro Poroshenko said in a statement on Monday.

The dates were discussed in a phone conversation among French President Francois Hollande, German Chancellor Angela Merkel and Russia's Vladimir Putin.

Poroshenko said the leaders highlighted the need to implement the next steps of a ceasefire plan agreed in the first round of talks in Minsk in September, which were aimed at ending the separatist conflict in Ukraine's eastern territories that has killed over 4,700 people.

"The participants agreed on the necessity of implementing all points of the Minsk agreement, including the question of the ceasefire ... the withdrawal of heavy weapons and also the immediate release of all hostages," Poroshenko said in a statement.

The September truce was flouted by both sides, but violence has lessened significantly in December, raising hopes of further talks, although previous plans have been postponed.

The uprising by the separatists, who oppose central rule by Kiev and seek union with Russia, began a month after Russia annexed the Black Sea peninsula of Crimea from Ukraine in March.

The pro-Western authorities in Kiev accuse Russia of orchestrating the uprising in the east after the ouster of a president sympathetic to Moscow. The Kremlin denies it is behind the revolt.