The treaty came in direct response to Cuba's invasions of Zaire from Angola in 1977 and in 1978. Mobutu and Kaunda's support for National Liberation Front of Angola (FNLA) and the National Union for the Total Independence of Angola (UNITA) rebels during the Angolan Civil War and dos Santos' support for the Front for the National Liberation of the Congo in Zaire led to repeated clashes in the 1970s.