OSCE personnel will monitor 10 flashpoint sites in eastern Ukraine where the ceasefire has been violated, Kiev says.
Leaders of France, Germany and Russia have agreed with Ukraine on the dispatch of OSCE monitors to 10 flashpoint sites on the country's eastern front line to shore up a shaky truce.
In a readout of a four-way telephone conversation published by the Ukrainian presidency, President Petro Poroshenko, German Chancellor Angela Merkel, French President Francois Hollande, and Russian President Vladimir Putin "supported Ukraine's suggestion to put monitors to all locations of ceasefire violations".
The intensified monitoring would start first and foremost with 10 flashpoints on the front line - Shchastya, Popasna, Stanitsa Luganska, Krymske, Avdiivka, Volnovakha, Granitne, Luganske, Shyrokine and the Donetsk airport area, the statement said.
Without going into such detail, the offices of Hollande, Merkel, and Putin said that greater and more direct involvement of the OSCE was needed and suggested the monitoring mission publish a daily report on its observations.
Merkel's spokesman Steffen Seibert said the leaders "agreed that the OSCE should play a more important role in monitoring the ceasefire and the withdrawal of weapons."
The French presidency noted progress on the ceasefire but said that there was improvement to be made.
The Kremlin said in a statement that the leaders "noted the importance of rigorous adherence to the ceasefire and continuation of pull back of heavy weapons", also advising that the OSCE mission "regularly publishes information" about the process.
Ukraine's security spokesman Anatoliy Stelmakh meanwhile reported no overnight casualties on Tuesday morning, but said the rebels violated the ceasefire six times between 9pm and 5am.
In addition, he said the rebels shelled the village of Pisky near the Donetsk airport, fired at Avdiivka from a tank and attacked Opytne with a grenade launcher.
Both villages are not far from the rebel hub Donetsk.
He added there was combat in Lugansk region near the village of Sokolnyki in the morning.
Ukrainian Foreign Minister Pavlo Klimkin on Tuesday called for an expansion of international monitoring.
"The situation on the ground is very difficult and tense despite a declared ceasefire. We still have many shells thrown by terrorists" in eastern Ukraine, Klimkin told reporters in Tokyo.
"There was always a problem of lack of trust in relations between Ukraine and Russia ... we can't rely on any kinds of agreements between us and Russians.
"And exactly because of that we need (a) consistent position of the whole international community for defending Ukraine peace and Ukrainian territorial sovereignty and territorial integrity."
Klimkin added: "What we need is, of course, at least a minor confidence and it could be provided by stopping any kind of shelling ... and clear monitoring and verification by the OSCE monitoring mission.
"We've been working on an additional stabilisation component - it could be a UN mission, it could be a EU mission or (both) of them."