This article studies the Anglo-Nigerian negotiations for a Royal Navy training team during the Nigerian Civil War against the background of Africa’s ‘phoney’ Cold War and Britain’s global strategic withdrawal. This allows it to show Britain’s diplomatic manoeuvres to simultaneously prevent provoking debilitating opposition against its tightrope policy of supporting Federal Nigeria against Biafra and safeguard its significant, predominantly economic – particularly oil – interests in Nigeria. Initially inconvenienced by the Nigerian request for a naval training team, British policymakers gradually agreed to send one after the war, then promised to do so already before, and, after the foreign policy establishment had overcome the Ministry of Defence’s resistance, finally sent out Royal Navy officers to Nigeria before the end of hostilities. In this process, the Nigerians had allies in the British High Commission in Lagos and the Foreign (and Commonwealth) Office, as well as substantial leverage as a result of Indian and Soviet competition in the Nigerian market for military assistance. Yet this leverage was mitigated by the Federals’ preference for British over Indian military assistance, and fear of becoming too reliant on Moscow. Not only in the British, but also in the Nigerian case, diplomatic concerns thus outweighed the military rationale for the naval training team, and this ‘diplomacy of military assistance’ contrasts with the basic tenor of the theoretical literature on military assistance in civil wars.