Rebels in Sudan's western Darfur region say government-backed Arab militias have broken a recent ceasefire agreement and as a consequence they may pull out of planned peace talks, media reports said Friday.

"The Janjaweed militia have burned down several villages just after we signed the peace agreement and many civilians mainly women and children have been killed", rebel spokesman Abdallah Abdel Karim told the BBC.

Karim said 32 civilians had been killed and several villages torched on Wednesday.

The 45-day humanitarian ceasefire agreement was signed on April 8 in Chad by the Sudanese government and the Sudan Liberation Movement (SLM) and Justice and Equality Movement (JEM).

It came after the U.N. Security Council had voiced "deep concern" over the humanitarian situation in Sudans Darfur region.

Both the U.N and the U.S have labelled what is going on in Darfur "ethnic cleansing".

Peace talks aimed at finding a final solution to the conflict are due to start on April 24.

Secretary General Kofi Annan said last week the international community must be ready to take swift and appropriate action against Sudan, if the Khartoum government denies aid workers access to Darfur.

This week, the human rights watchdog Human Rights Watch (HRW) said the ceasefire agreement needed to be watched closely.

"Without the international spotlight, the Sudanese government is unlikely to disarm and disband its Arab militia, re-establish security in the rural areas, or guarantee the safety of displaced persons who wish to return home for planting season-crucial benchmarks for any improvement in the situation" said HRW said in a statement.

The U.N. Under-Secretary General for humanitarian affairs, Jan Egeland, is due to travel to Darfur next week to assess the situation.

Meanwhile, a team from the U.N. High Commission for Human Rights is on the Chad-Sudan border, interviewing refugees about alleged human rights abuses by the Arab Janjaweed militias.

The two rebel groups last year launched a revolt against the government in Khartoum saying it had armed Arab militias to loot and burn African villages.

An estimated 670,000 people, most of them black African Muslims, have been displaced by the Darfur fighting, and over 100,000 have fled to neighbouring Chad.

The U.N. has asked the international community for $115 million to help the people of Darfur cope with the effects of the civil conflict - Sapa-DPA.