The European Union will provide additional support for an African military mission in Mozambique as Islamist attacks threaten gas projects designed to reduce the EU's dependence on Russian energy resources.

Mozambique has the third largest proven gas reserves in Africa. But the southern African country has been fighting Islamic State-linked militants in the northernmost gas-rich province of Cabo Delgado since 2017.

The EU said governments agreed to give 15 million euros to the Southern African Development Community (SADC) mission in Mozambique (SAMIM), which is fighting insurgents.

In an internal report seen by Reuters, the EU warned of a very unstable situation in northern Mozambique, despite the SADC mission and the separate intervention of troops from Rwanda who managed to contain the rebels.

The financial support was announced a day after Mozambique reported that at least six people had been beheaded and an Italian nun killed by rebels in the northern province of Nampula.

The funds come in addition to the 1.9 million euros already provided by the EU to SAMIM and the 89 million euros to the Mozambican armed forces.