The British Government, which had denounced UDI as illegal, began broadcasting BBC programmes into Rhodesia by building a radio relay station in Francistown, in the then Bechuanaland Protectorate, now Botswana. The Rhodesian Government retaliated by clandestinely building a 400 000 watt transmitter nicknamed "Big Bertha", in order to jam the signal from the smaller BBC transmitter. Programmes about Rhodesia were subjected to jamming, but other programmes were not affected. In 1968, the BBC ceased broadcasting from Francistown, and the relay station was transferred to the Government of Botswana.