The EU has suspended all security cooperation with Niger after the country's army took power in a coup.It comes shortly after the US declared its "unflagging support" for ousted president Mohamed Bazoum - seen as a key Western ally in the fight against Islamist militants.On Friday the head of the presidential guards unit Gen Abdourahmane Tchiani declared himself Niger's new leader.He said insecurity, economic woes and corruption led him to seize power.But there are now concerns in the West about which countries the new leader will align with.Niger's neighbours, Burkina Faso and Mali, have both pivoted towards Russia since their own coups.EU foreign policy chief Josep Borrell joined the US and France in refusing to recognise the coup leaders and said security cooperation and budgetary aid was being suspended indefinitely.Also on Saturday the African Union called on the Niger army to return to base within 15 days.Mohamed Bazoum - Niger's first elected leader to succeed another since independence in 1960 - is currently thought to be in good health, and still held captive by his own guards.On Friday evening US Secretary of State Antony Blinken warned those detaining him that "hundreds of millions of dollars of assistance" was at risk.However, the leader of Russia's Wagner mercenary group has reportedly described the coup as a triumph.