Two Rwandan women are to sue the United Nations for alleged complicity in the Rwandan genocide.

Two Australian lawyers have been engaged to act for the women, whose families were murdered by Hutu militants during the 1994 genocide.

The case is believed to be the first time that the UN has been sued for complicity in such crimes.

The women claim that the UN soldiers whose task it was to defend their families either handed them over to their killers or ran away.

One of the women, Anonciata Kavaruganda, is the widow of Joseph Kavaruganda, a Rwandan Supreme Court judge who was killed because he sympathised with the Tutsis.

Mrs Kavaruganda says the Ghanaian UN soldiers who were supposed to be protecting her family were drinking and socialising with the Hutus while she and her children were being tortured.

UN staff 'ran away'

The other woman is Louise Mushikiwabo, whose brother, Lando Ndaswinga, the only Tutsi cabinet minister in the Hutu-dominated Rwandan Government, was shot, along with their mother.

Ms Mushikiwabo says the UN "protectors" ran away when the killers came.

Former South Australian crown prosecutor Michael Hourigan and prominent human rights lawyer Geoffrey Robertson are to take up the women's case.

Mr Hourigan, who formerly worked in Kigali as an investigator with the UN International Criminal Tribunal for Rwanda, said it was not clear what court might hear the case.

A damning independent report released in December said the UN was guilty of a catalogue of failures during the genocide.

In response, UN Secretary-General Kofi Annan expressed bitter regret and admitted the UN's failings in the handling of the Rwandan genocide.