Espérance Nyirasafari said she had "done a horrible thing” for taking part in that function, an act that the governing RPF party said “threatens the unity of all Rwandans”.

Other party members who took part have also apologised.

One vice-mayor resigned on Monday night following the incident.

The clan leader who was introduced at the function that took place early this month, also said sorry.

The issue around ethnicity in Rwanda remains sensitive, almost three decades after the genocide where around 800,000 Tutsi and moderate Hutu were killed in 100 days.

Mrs Nyirasafari's apology puts her political influence and position in doubt.

She has previously served as a national prosecutor, minister of gender and minister of sports and culture.

In her apology she said she regretted not "doing anything” to stop the clan meeting.

Public apologies aren’t new for the RPF and the opposition says their purpose is to shame and discredit officials who otherwise would give different ideas on policies.