MANILA (UPDATE) - Supreme Court Senior Associate Justice Antonio Carpio said Tuesday that he would decline his automatic nomination for the chief justice post.

Chief Justice Lucas Bersamin is set to retire on October 18 at the age of 70, just 8 days ahead of Carpio's retirement on October 26 after an 18-year stint in the High Court.

"I am declining because there are only 8 days left from the vacancy to my compulsory retirement," Carpio told ABS-CBN News in a text message.

One of the longest-serving Supreme Court justices, Carpio is a staunch advocate of the Philippines' territorial claims to the South China Sea.

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Supreme Court Associate Justice Marvic Leonen said Monday that he also turned down his automatic nomination because "I will be able to do what I do best for our people in my current position."

Meanwhile, Justice Secretary Menardo Guevarra said Associate Justice Jose Reyes Jr. submitted his application for the chief justice post.

Associate Justices Estela Perlas-Bernabe, Diosdado Peralta, and Andres Reyes Jr. accepted their nominations, while their colleague Alfredo Benjamin Caguioa declined, said Guevarra, a member of the Judicial and Bar Council.

The deadline for applications and acceptance of nomination is on Tuesday.

- Report from Mike Navallo, ABS-CBN News