The armistice also envisages the withdrawal of heavy weapons by both sides from the front line which should begin no later than the second day after the ceasefire, and the establishment of a security zone with a width of 50 to 70 kilometers in southeastern Ukraine.

The four leaders signed in the declaration, saying "they are strongly convinced that a peaceful settlement is the sole option (for the resolution of Ukraine crisis)," a position that distinguish them from US President Barack Obama who said three days ago that "the possibility of (arming Kiev with) lethal defensive weapons is one of those options that is being examined."

"Against this background, the position of the US looks like a dissonance as it repeatedly called for arming Kiev," said Sergei Naryshkin, Speaker of Russian State Duma, or the lower house.

Though the deal gives a chance for peace and survival for people in eastern Ukraine, a fact that can hardly be neglected is that it is a product of compromise.

"There is no guarantee that the agreement will be long-lived, because the fresh agreement, to some extent, is a replica of the September deal," said Igor Korotchenko, editor-in-chief of Russia' s The National Defense magazine.

"It is unclear whether Poroshenko has enough resources to persuade domestic interest groups to implement the agreement, and the political status of Donbass is still up in the air," he told Xinhua.

The first issue for now is to ensure a full implementation of the new deal, which would lay a solid foundation for further progress.

"The cooperation among all parties is necessary in order to move in the constructive direction," said Ilkka Kanerva, president of the Parliamentary Assembly of the Organization for Security and Cooperation in Europe.