MANILA, Philippines—Makati City Vice Mayor Ernesto Mercado has filed his certificate of candidacy for mayor under the Nacionalista Party of Senator Manuel Villar Jr.

In a check with the city’s Commission on Elections office, the Philippine Daily Inquirer learned that Mercado and his councilors seeking reelection filed their candidacy papers on Sunday, without much fanfare.

Mercado has been vice mayor to exiting Mayor Jejomar Binay for the past nine years.

The two allies are said to be having a rift lately and Binay might field his son, Councilor Jun-Jun Binay as his mayoral candidate against Mercado.

Mercado has yet to name his vice-mayoral bet.