Andrew Mitchell will be forced to give evidence to a Commons committee next week, as MPs demand answers about why he reinstated aid to Rwanda despite concerns over human rights abuse.
Mitchell reversed the aid cut to Rwanda on his last day as international development secretary, despite howls of protest from the UN and human rights groups.
The ongoing row became a subplot to his difficulties with the police outside Downing Street which eventually cost him his job as chief whip.
Now the international development committee has demanded Mitchell answer questions about his decision next Thursday, followed the next week by his successor, Justine Greening.
Rwanda is understood to be funding rebel militias – some of whom are believed to use child soldiers – in the Democratic Republic of the Congo.
It is also accused of unlawful detention and torture at home and of trying to assassinate Rwandans in London.
But experts on the region say Mitchell developed a close personal friendship with Rwandan leader Paul Kagame and became overly loyal towards his aid programme in the country, which was one of the first initiatives David Cameron started in his campaign to get the Conservatives associated with overseas aid.