French energy giant Total has suspended operations at a site exploring a major gas field in northern Mozambique weeks after Islamist militants attacked a nearby town.
The company said that it was withdrawing all its staff because of the “evolving” security situation.
Dozens of people were killed in the March raid on the town of Palma.
Total’s $20bn (£14.6bn) gas liquification plant is the largest foreign investment in Africa.
Its Afungi site is near Palma which has been repeatedly attacked by militants linked to the Islamic State (IS) group.
During the 24 March attack, dozens of foreign contract workers and local people were besieged at the Amarula Palma Hotel.
The UN’s World Food Programme said last week that the March attack had caused tens of thousands to flee the area – adding to a growing humanitarian crisis.
The agency says many lack proper shelter, and malnutrition among children is on the rise.
The four-year insurgency in Cabo Delgado region has left more than 2,500 people dead and 700,000 displaced.
Mozambique’s President Felipe Nyusi has promised to restore peace in the restive Cabo Delgado province.
On Monday Total said it “expresses its solidarity” with the government and called on the authorities to restore security.
The halting of Liquefied Natural Gas (LNG) exploration is a big blow to Mozambique, analysts say.
Insecurity in the region has also affected local traders – the country’s main business association said small- and medium-sized firms had lost $90 (£64m).