Faustin Twagiramungu, Rwanda's prime minister after the 1994 genocide and a virulent critic of President Paul Kagame, died in exile in Belgium on Saturday aged 78, his party announced.
Twagiramungu served as Rwanda's premier from 1994 to 1995 and unsuccessfully ran for president in the 2003 elections won by Kagame, who has been in power ever since.
Twagiramungu later went into voluntary exile in Belgium, where he lived with his family, and became a fierce critic of Kagame's government, calling it a "cruel dictatorship".
His party, the Rwandan Dream Initiative, released a statement saying Twagiramungu died on Saturday morning without providing further details on the circumstances.
Government critic Victoire Ingabire, jailed on terrorism charges before being released in 2018, told AFP Twagiramungu "will never be forgotten in Rwandan politics and history" and was "a great fighter for democracy".