The UN human rights chief on Monday called on the international community to support reforms in the Middle East and urged vigilance in Libya amid fears of violent reprisals.

"The international community bears the great responsibility of extending its support in words and deeds to assist such indispensablereforms. It must do so with dispatch and firmness," said High Commissioner for Human Rights Navi Pillay.

She told the UN Human Rights Council that it should remain vigilant over the situation in Libya, despite having taken unprecedented action last Friday through a unanimous resolution that recommended the suspension of Libya.

The 47-member council in Geneva has also ordered an international probe into what it described as possible "crimes against humanity" carried out by Muamer Gaddafi's regime.

"The council should not relax its vigilance over Libya as the threat of violent reprisals against civilians still looms," she told told ministers and envoys gathered at the opening of its 16th session.

Beyond Libya, Pillay noted that the "illegal and excessively heavy-handed response of a number of governments is intolerable." "Repression of peaceful expression of dissent is also intolerable. I remind all those concerned that widespread and systematic attacks against the civilian population may amount to crimes under international law," she said.

Pillay noted that changes brought on by popular uprisings in the Arab world must be allowed to take root, in order to avoid backsliding into dictatorship.

"It is important that the changes now spurred by the uprisings take root before former entrenched interests begin to reassert themselves, or new threats emerge," she said.