Leading Sudanese politician and former prime minister Sadiq Al Mahdi died from a coronavirus infection three weeks after being admitted to hospital in the UAE, family sources said on Thursday. Al Mahdi, 84, was Sudan’s last democratically elected prime minister and was overthrown in 1989 in the military coup that brought former president Omar Al Bashir to power. British ambassador to Khartoum, Irfan Siddiq, offered his condolences. "Shocked and saddened to hear of the passing of Imam Alsadiq Almahdi," he wrote on Twitter. "A true patriot and leader of the nation. My deepest condolences to all the Sudanese people on this loss." Mr Siddiq ended his tweet with the Arabic transliteration for a phrase used among Muslims after someone's death: "May God have mercy on him. We belong to God and to him we shall return." Al Mahdi led the moderate Umma Party, one of the largest opposition parties under Al Bashir, and remained an influential figure in Sudanese politics. Al Mahdi’s family said he had tested positive for Covid-19 last month and was transferred to the UAE for treatment a few days later after a brief spell in hospital in Sudan. The Umma Party said Al Mahdi would be buried on Friday morning in Omdurman, the twin city of the capital Khartoum on the opposite bank of the Nile river. Al Mahdi had returned to Sudan in December 2018 after a year-long self-exile, just as protests over worsening economic conditions and Al Bashir's rule gathered momentum. His daughter, Mariam Sadiq Al Mahdi, deputy leader of the Umma Party, was among those detained during the demonstrations. While a successor to lead the party has not yet been announced, she has been the most visible party figure in political negotiations and the media in recent years. Opposition parties were weakened greatly under Al Bashir’s three-decade regime, and are jostling for power with the military during Sudan’s transition, making the Umma Party’s continued unity crucial to maintaining the balance of power. After the military forced Al Bashir from power, Al Mahdi pushed for a transfer to civilian rule, warning of the risks of a counter-coup and calling for the powerful Rapid Support Forces paramilitary to be integrated.