The Philippines' security council will verify an alleged assassination threat by Vice President Sara Duterte against President Ferdinand Marcos Jr., a top official said on Sunday, describing it as a "matter of national security".

Philippine Vice President Sara Duterte yesterday failed to show up for a meeting with government investigators after being labeled the “self-confessed mastermind” of a plot to kill Philippine President Ferdinand Marcos Jr.

The presidential security agency said the vice president's threat on President Marcos was "a matter of national security." Duterte said she would have the president killed if she herself were to be killed.

The threat by Sara Duterte, daughter of firebrand former President Rodrigo Duterte, is the latest twist in a dramatic spat between the powerful families.

Philippine President Ferdinand Marcos Jr said on Friday that any impeachment complaint against his estranged vice president Sara Duterte, who over the weekend made threats against his life, would only tie down Congress and not help people.

Government officials were probing Philippine Vice President Sara Duterte after she said she had instructed someone to assassinate President Ferdinand Marcos Jr. if she were killed.

Philippine President Ferdinand Marcos Jr said on Friday it would not be good for the country if an impeachment complaint is filed against his estranged vice president. Marcos told reporters lodging an impeachment case against Vice President Sara Duterte will not make any difference to people's lives and would only tie down Congress.

Philippine Vice President Sara Duterte on Friday failed to show up for a meeting with government investigators after being labelled the "self-confessed mastermind" of a plot to kill President Ferdinand Marcos.

Vice President Sara Duterte has asked the National Bureau of Investigation (NBI) to postpone a hearing on her alleged death threat against President Marcos Jr.