The geopolitical situation tilted further against Smith in December 1974 when the South African Prime Minister B. J. Vorster pressured him into accepting a détente initiative involving the Frontline States of Zambia, Tanzania and Botswana (Mozambique and Angola would join the following year). Vorster had concluded that Rhodesia's position was untenable; in his view, it made no sense to maintain white rule in a country where blacks outnumbered whites by 22:1. He also believed that South African interests would be better served by collaborating with black African governments over a Rhodesian settlement; he hoped that success in this might win South Africa some international legitimacy and allow it to retain apartheid. Détente forced a ceasefire, giving the guerrillas time to regroup, and required the Rhodesians to release the ZANU and ZAPU leaders so they could attend a conference in Rhodesia, united under the UANC banner and led by Muzorewa. When Rhodesia stopped releasing black nationalist prisoners on the grounds that ZANLA and ZIPRA were not observing the ceasefire, Vorster harried Smith further by withdrawing the South African Police, which had been helping the Rhodesians patrol the countryside. Smith remained stubborn, saying in the run-up to the conference that "We have no policy in Rhodesia to hand over to a black majority government" and that his government instead favoured "a qualified franchise for all Rhodesians ... ensure that government will be retained in responsible hands for all times".