Russian President Vladimir Putin called for an extension of a ceasefire in Ukraine's southeastern regions, the Kremlin said on Monday after phone talks with European Union (EU) leaders.

"Putin stressed the need to extend the ceasefire and create a reliable monitor mechanism with the active role of the OSCE ( Organization for Security and Cooperation in Europe)," the Kremlin said in a statement after Putin held a four-way teleconference with German Chancellor Angela Merkel, French President Francois Hollande, and Ukrainian President Petro Poroshenko.

The leaders called for organizing the next round of consultations between representatives of Kiev and south-eastern regions as soon as possible, the Kremlin said. Two previous rounds of inconclusive talks produced no tangible results, with no end to weeks of fighting in sight.

The four leaders also agreed that the four countries' foreign ministers would hold urgent talks to work out the practicalities following the four-way talks, it said.

The deadline for the current ceasefire in violence-hit eastern Ukraine runs out at 1900 GMT on Monday. On June 20, Poroshenko announced a unilateral ceasefire plan aiming at peacefully resolving the conflict in eastern regions, calling on the rebels to lay down weapons and start peace talks with the government in Kiev.

Also on the day, the Elysee for its part said that Putin and Poroshenko agreed to work on implementing a cease-fire between separatists and Ukrainian authorities.

The four leaders vowed to set "an effective mechanism" to reinforce border controls, it said in a communique, adding that they also agreed to work on the release of more hostages and prisoners and the organization of substantial tripartite negotiations. Top diplomats of Russia and Ukraine were scheduled to meet later in the day, it added. The turmoil in the largely Russian-speaking east of Ukraine erupted in April after street protests in Kiev toppled former leader Viktor Yanukovych.