Nigeria's nationalisation of BP on 31 July 1979 — timed for the opening of the Lusaka CHOGM — was the proximate trigger for Margaret Thatcher's reluctant agreement to convene the Lancaster House conference (10 September – 21 December 1979) that ended UDI Rhodesia. Foreign Minister Henry Adefope led the Nigerian delegation that mediated between ZANU (Mugabe), ZAPU (Nkomo) and the Muzorewa-Smith bloc; the Patriotic Front's eventual signature was preceded by a private Adefope–Mugabe meeting in Lagos in October 1979.
In the first eighteen months after Zimbabwean independence (18 April 1980), Nigeria provided: US$10 million in direct budget support; 200 Nigerian secondary-school teachers seconded to fill the post-independence white-flight gap (the Technical Aid Corps, formally institutionalised in 1987 partly on the basis of this experience); scholarships for 150 Zimbabwean students at Nigerian universities; and the secondment of senior Nigerian civil servants to the Ministry of Education in Harare. President Shagari made the first state visit of the new Republic to Harare in October 1980. See Zimbabwe relations.