In a telephone call with the President, Ban expressed his grave concern and emphasised that there must be no resort to violence.

He also welcomed President Yanukovich's assurances that consultations would be initiated to defuse the situation, according to a readout of the conversation from Ban's spokesperson.

The wave of demonstrations was sparked by a Government decision on 21 November to not sign an agreement on broader integration with the European Union.

Following the protests that followed, Ban appealed to all parties to act with restraint, avoid any further violence and to uphold the democratic principles of freedom of expression and peaceful assembly.

In Sunday's call, the top UN official also congratulated Yanukovich on a successful chairmanship during this year of the Organization for Security and Co-operation in Europe (OSCE) Chairmanship and of the ministerial meeting held on 5 and 6 December in Kyiv.

The meeting, attended by representatives of the 57 participating states, focused on addressing protracted conflicts, energy and the environment, and efforts to address transnational issues, such as religious freedoms and Roma, according to the OSCE website.

Secretary-General Ban Ki-moon speaks on the telephone [file photo]. UN Photo/Paulo Filgueiras