On August 19, 1889 J. Buchanan, the acting British consul in Nyasaland, issued what was to be the first of many declarations protesting Portuguese actions in the Makololo country and in the Shire regions. Serpa Pinto had been leading Portuguese scientific expeditions into these areas, and Britain feared a threat to its interests.
On October 23, 1889 Petre, the British Minister in Lisbon, warned that Great Britain would oppose any Portuguese action which would threaten the interests of Great Britain. In addition, on October 29, the British government granted a charter to the British South Africa Company which gave it rights and governmental powers in the area north of the Transvaal and west of Mozambique, areas presumed to be threatened by the Portuguese expeditions.
In November, Petre confronted the Portuguese Minister of Foreign Affairs, Gomes, with information regarding the number of troops now escorting the expedition. Gomes reiterated Pinto's statements as to the peaceful nature of the expedition along with assurances that the troops were solely in case the Makololo should attack. Petre accused Gomes of preparing to attack the Makololo in order to conquer the area. Gomes, sent a dispatch to Britain citing the Portuguese claims to the disputed area. (Although this dispatch was dated November 29, it was not relayed to the British Foriegn Office until December 5.)
Having learned of military confrontations between African natives and Portuguese troops in Makololo country, on December 18, 1889, Petre relayed British requests that the Portuguese government refrain from attacking British settlements. Gomes replied on December 20 that Portugal had organized a scientific expedition which could not be considered military in nature. Six days later Pinto cabled Lisbon that Portuguese authority had been established in Makololo country.
The British responded with a show-of-strength as the Atlantic squadron arrived off Las Palmas on December 29. On January 2, 1890, another British squadron arrived at Gibraltar.
Petre sent a note to Gomes on January 6, summarizing British demands for assurance that Portugal had no intentions of settling the disputed territory or infringing on British claims. Gomes replied, once again, that Pinto's expedition was not intended as a military foray, but he also stated that Portugal could not recognize British claims to a territory which was historically Portuguese.
Britain, having meanwhile learned of the Portuguese victory in Makololo, issued an ultimatum on January 10, protesting Portuguese actions in the interior and demanding the withdrawal of all forces and administrative control in the Makololo country and surrounding areas. Noting that Portugal had already capitulated to many of the demands outlined in the earlier British note (December 18, 1889), Gomes suggested that both sides accept the status quo.
Now several more British naval forces appeared at various points, and a number of rumors circulated regarding British intentions to occupy Lourenco Marques, Quelimane and St. Vicente if their demands were not met.
Gomes conveyed the Portuguese Council's decision to yield unconditionally on January 12, and orders were given to remove Portuguese forces from the Shire and Mashonaland.