On 10 September , the Prime Minister announced to the nation that certain areas of the country would be placed under a variation of martial law , which he said would be applied in particular regions as and when needed . He declared Rhodesia 's intent to " liquidate the internal workings of those organisations associated with terrorism " , and warned neighbouring countries to prepare for " any defensive strikes we might undertake " against guerrilla bases in their respective territories . He claimed that the war had escalated because Britain and the United States were supporting the Patriotic Front . William Irvine , the co @-@ Minister of Transport , warned the guerrillas that Rhodesia " w [ ould ] not let these innocents go unavenged " .