The Pwersa ng Masang Pilipino (PMP), headed by former president Joseph Estrada, and the Partido Demokratiko Pilipino-Lakas ng Bayan (PDP–Laban), headed by Vice President Jejomar Binay, signed a coalition agreement on April 4, 2012, for the 2013 elections, forming the United Nationalist Alliance (UNA).

On July 1, 2015, Binay relaunched the United Nationalist Alliance as the major opposition party at the Makati Coliseum in Makati days after he resigned from the Cabinet of President Noynoy Aquino, despite the absence of Manila Mayor Joseph Estrada which become neutral due to Sen. Grace Poe possible presidential bid.

Aquilino Pimentel III and Gregorio Honasan, Representatives Jack Enrile and JV Ejercito, and 2010 senatorial candidate Joey de Venecia.

[8] On June 11, 2012, UNA formally included Zubiri in its line-up, together with Cebu Governor Gwendolyn Garcia and Zambales Representative Mitos Magsaysay.

[15] On February 21, 2013, UNA dropped Chiz Escudero, Loren Legarda and Grace Poe from their senatorial slate as a result of their non-attendance in their political rallies.