As late as 1888, the British Foreign Office declined to accept responsibility for protecting the rudimentary British settlements in the Shire Highlands, despite unsubstantiated claims by the African Lakes Company of Portuguese interference with their trading activities. However, it also declined to negotiate with the Portuguese government on their claim that the Shire Highlands should be considered part of Portuguese East Africa, as it was not regarded by the Foreign Office as under effective Portuguese occupation. In order to prevent Portuguese occupation, the British government sent Henry Hamilton Johnston as British consul to Mozambique and the Interior, with instructions to report on the extent of Portuguese rule in the Zambezi and Shire valleys and the vicinity, and to make conditional treaties with local rulers beyond Portuguese jurisdiction. These conditional treaties of friendship did not amount to the establishment of a British protectorate but prevented those rulers from accepting protection from another state. On his way to take up his appointment, Johnston spent six weeks in Lisbon in early 1889 attempting to negotiate an acceptable agreement on Portuguese and British spheres of influence in Central Africa. The draft agreement reached in March 1889 would have created a British sphere including all the area west of Lake Nyasa and also Mashonaland but not including the Shire Highlands and Lower Shire valley, which were to be part of the Portuguese sphere. This went beyond what the Foreign Office was prepared to accept, and the proposal was later rejected.