Tunisian President Kais Saied sacked Prime Minister Kamel Maddouri less than a year after his appointment amid a faltering economy and a growing number of migrants arriving from countries in sub-Saharan Africa.

Maddouri was replaced by Sara Zaafarani, who is an engineer and has been minister of equipment and housing since 2021. She is Tunisia's third prime minister in less than two years.

In recent months, Saied has sharply criticised the performance of ministers, saying many have not met the required standards and that the expectations of the Tunisian people are high. Last month, he sacked Finance Minister Sihem Boughdiri.

In a meeting broadcast on the presidency's Facebook page, Saied called on Zaafarani "to further coordinate government action and overcome obstacles to meet the expectations of the Tunisian people".

Tunisians have complained about deteriorating public services from health to transport and utilities.

"Criminal gangs are active in many public facilities. It is time to put an end to them and hold every official accountable, regardless of their position and the nature of their negligence or complicity.", Saied said in a speech at a National Security Council meeting on Friday.

Economic growth has not exceeded 1.4% in the past year, and the North African country's public finances face a severe crisis that has led to shortages of key commodities including sugar, rice and coffee.

"We will continue the liberation battle until justice prevails for all citizens ... We will continue to thwart all conspiracies", Saied said.

Tunisia is also facing widespread criticism over an unprecedented migrant crisis, as thousands of people from sub-Saharan Africa head to the country in an attempt to reach Europe.

Thousands of migrants are living in tents in forests in southern towns such as Amra and Jbeniana after authorities prevented them from travelling across the Mediterranean.

While the migrants frequently clash with local residents who want them deported from their area, local human rights groups accuse the authorities of racist rhetoric and incitement against migrants.

Saied seized extra powers in 2021 when he shut down the elected parliament and moved to rule by decree before assuming authority over the judiciary.

The opposition described the move as a coup.