UN Secretary-General Ban Ki- moon said on Friday that the UN would "stand guided by any decision the Security Council would make" on the possibility of peacekeeping mission in eastern Ukraine.

Ban made the remarks in a telephone conversation with Ukrainian Foreign Minister Pavlo Klimkin while expressing his hope for a firm implementation of ceasefire agreement reached on Feb. 12 in the Belarusian capital of Minsk.

UN chief commended the leadership displayed by President Poroshenko in efforts to find a peaceful resolution to the ongoing conflict in eastern Ukraine and voiced his concern at the still dangerous situation on the ground, UN Spokesperson Stephane Dujarric told a daily briefing.

Ukrainian President Petro Poroshenko on Thursday called for deploying international peacekeepers in the war-torn eastern Ukraine to observe the implementation of the ceasefire deal between government troops and pro-independence fighters.

"The best format for us is the police mission of the European Union (EU), which would operate on basis of the decision of the United Nations Security Council," Poroshenko said during a joint press conference with Johannes Hahn, the EU commissioner for European Neighborhood Policy and Enlargement.

The Ukrainian National Security and Defense Council (NSDC) will soon appeal to the UN Security Council with a request for the deployment of an international peacekeeping mission, Poroshenko said.

In response, Moscow warned that Kiev's call for the deployment of international peacekeepers may disrupt the Minsk peace accord.

On Feb. 12, leaders of Ukraine, Russia, Germany and France announced a peace deal which envisages a ceasefire between Ukrainian forces and independence-seeking insurgents starting on Feb. 15, followed by the withdrawal of heavy weapons from the front line and constitutional reform to give eastern Ukraine more autonomy.

Since the new truce came into force on Feb. 15, the ceasefire has been generally observed despite sporadic violations, particularly in the strategic transport hub of Debaltseve where fighting has been raging over the past days, which puts the parties concerned on edge about the situation in eastern Ukraine.

Debaltseve, a small railway hub lying between the two rebel strongholds of Donetsk and Lugansk, has become one of the main flashpoints in recent weeks, as some 8,000 Ukrainian troops have reportedly been encircled by militia in Debaltseve, a claim denied by Kiev.

The UN's Office for the High Commissioner for Human Rights on Friday voiced deep concern over the fate of civilians, as well as the captured or wounded Ukrainian servicemen in the Debaltseve area, saying "it is unclear how many civilians were trapped while fighting raged there, and how many have been wounded or killed, or whether they now have access to medical and other basic services."

The office also expressed regret that the Organization for Security and Cooperation in Europe (OSCE) monitors "were not, and still have not been allowed access to this area."

The OSCE is to serve as a mediator and observer of the implementation of the Minsk agreement reached by the Ukrainian conflicting sides. On Tuesday, top leaders of Russia, Germany and Ukraine have agreed on the monitor mission of the OSCE in eastern Ukraine.

According to the conservative estimate of the Office, as of Wednesday, the death toll has risen to nearly 5,700 and the wounded has reached at least 14,100 in eastern Ukraine.