The Pacts of May (Spanish: Pactos de Mayo) are four protocols signed in Santiago de Chile by Chile and Argentina on 28 May 1902 in order to extend their relations and resolve its territorial disputes. The disputes had led both countries to increase their military budgets and run an arms race in the 1890s.
1. - Acta Preliminar: Argentina renounces to intervene in the Chilean affairs in the Pacific Ocean
2. - Tratado general de Arbitraje: Frame contract to define how to resolve territorial controversies
3. - Convención sobre Limitación de Armamentos Navales: The most famous of the protocols is the arms control treaty. It stated that Chile and Argentina sold off warships they had under construction in Europe and the disarmament of some ships already in service. As a consequence of territorial disputes both countries had begun to increase their military budgets and an arms race ensued in the 1890s. Of longer-lasting importance, the pact resolved the power projection competition by assigning each country a sphere of influence: Chile in the Pacific and Argentina in the Atlantic and Rio de la Plata. According to Rizzo Romano, it is the first arms control pact.
4. - Agreement: to ask the Edward VII of the United Kingdom the demarcation ad hoc of his award of 1902.
During the Beagle Channel Arbitration Argentina brought forward the argument that the Pactos de Mayo implied a demarcation clause between both countries: Chile at the Pacific and Argentina at the Atlantic. Chile denied the argument; the pactos are not a border treaty and therefore no place is named as limit between the Pacific and the Atlantic, the Cape Horn is limit between both oceans is an Argentine convention.