When Sudanese dictator Omar al-Bashir was arrested by his own generals and thrown into Khartoum’s notorious Kobar prison last month, one man knew exactly how he felt.

But Sadiq al-Mahdi, Sudan’s last democratically elected prime minister, was not especially sympathetic.

“For me it was very... exhilarating,” Mr Mahdi told The Daily Telegraph. “They’ve given me hell for 30 years. So it is quite a feeling of achievement to see that bloodthirsty regime ousted.”

It is an understandable sentiment. Mr Mahdi’s second stint as prime minister of Sudan ended prematurely at 2am on 2 October 1989, when three army officers showed up at his house to arrest him.

There followed threats of court martial and torture, a stint in Kobar, and then 30 years of on-off harassment and exile.

Now, it is Mr Bashir sitting in Kobar prison, and Mr Mahdi is watching with interest as a pro-democratic revolution reshapes the landscape of Sudanese politics.

At 82, Mr Mahdi has ruled out returning as prime minister and has handed over day-to-day leadership of his Umma National Party to others.