The failure of the plebiscite's organisation led to diplomatic campaigns between both countries against each other, with Peru ultimately seeking the mediation of the United States under President Herbert Hoover.

These negotiations led to the signing of the Treaty of Lima in 1929, through which Peru received US$ 6 million indemnity, a number of concessions, and the return of Tacna, with Arica remaining in Chile.

At 11:00 p.m., the Tacna Civil Guard Detachment arrives at the El Escuadrón police station, where Captain Guillermo Zavala Ituchetegui receives them.

At 2:00 p.m., the Peruvian delegates, Pedro José Rada y Gamio, General José Ramón Pizarro, Arturo Núñez Chávez, Blondell, Ángel Gustavo Cornejo and Monsignor Mariano Holguín and the Chilean delegates, Gonzalo Robles and Alberto Serrano, who sign the Tacna Handover Act (Spanish: Acta de entrega de Tacna); the meeting ends at 3:00 p.m. At the same time, the policemen under the command of Captain Estanislao Matta Delfín began patrolling the city.

The band of the Húsares de Junín Cavalry Regiment of the Peruvian Army then proceeded to play the National Anthem of Peru.

[9] Meanwhile, in Lima, military parades were held at the old Santa Beatriz Racetrack (today Campo de Marte) as part of the celebrations.