United Nations aid workers in eastern Madagascar are helping local officials mount relief efforts in the wake of Tropical Storm Hubert, which has killed dozens of people in the Indian Ocean country and left an estimated 11,000 others homeless.

The African Union has put sanctions on Madagascar's leader Andry Rajoelina, after he failed to meet a deadline to set up a unity government. Mr Rajoelina and 108 of his backers will face travel restrictions and have any foreign assets frozen, the AU said.

This latest report from the International Crisis Group, analyses the underlying causes and offers a new approach to unlock the negotiation stalemate. Power-sharing agreements signed in Maputo in August 2009 and Addis Ababa in November offered opportunities to promote a consensual transition. But though he signed, de facto President Andry Rajoelina and his entourage have blocked implementation of the accords, so were hit by African Union (AU) personal sanctions on 17 March.

Madagascar's history is marked by a struggle for political control. By 1700, France and England had attempted to establish settlements, while the rulers of the island's many kingdoms fought among themselves for dominance. Madagascar gained independence in 1960, but since then it has been plagued by assassinations, military coups and disputed elections.

Tensions between street traders and the city authorities in Madagascar's capital, Antananarivo, are mounting as hundreds of recently unemployed textile industry workers compete with established informal traders; textile factories have been closing since the country was suspended from a preferential trade agreement with the US.