Madagascar President Andry Rajoelina said on Monday he was dissolving the government following youth-led protests over water and power cuts in which the United Nations says at least 22 people have been killed and more than 100 injured.

Inspired by the so-called "Gen Z" protests in Kenya and Nepal, the three days of demonstrations are the largest the Indian Ocean island has seen in years, and the most serious challenge Rajoelina has faced since his re-election in 2023.

"We acknowledge and apologise if members of the government have not carried out the tasks assigned to them," Rajoelina said in speech on state broadcaster Televiziona Malagasy (TVM).

The president said he wanted to create space for dialogue with young people, and promised measures to support businesses affected by looting.

"I understand the anger, the sadness, and the difficulties caused by power cuts and water supply problems. I heard the call, I felt the suffering, I understood the impact on daily life," he said.

The United Nations High Commissioner for Human Rights said the casualties include protesters and bystanders killed by members of the security forces, but also others killed in subsequent widespread violence and looting by individuals and gangs not associated with the protesters.

Madagascar's ministry of foreign affairs rejected the casualty figures reported by the UN, saying the data did not come from competent national authorities "and are based on rumours or misinformation."

On Monday protesters gathered at a university where they waved placards and sang the national anthem before attempting to march towards the city centre, footage from 2424.MG news channel showed.

Police fired teargas to disperse the crowd, after authorities declared a dusk-to-dawn curfew last week.

The protesters have adapted a flag used in Nepal where protesters forced the prime minister to resign this month and have also used similar online organisation tactics as protests in Kenya last year that culminated in the government scrapping proposed tax legislation.

Rajoelina first came to power in a 2009 coup. He stepped down in 2014 but became president again after winning the 2018 election, and secured a third term in a December 2023 poll that his challengers said was marred by irregularities.