President Rodrigo Duterte has dismissed two top executives of the Social Security System by not renewing their appointments, an official said on Monday.

In a press briefing, Presidential Spokesperson Harry Roque said Executive Secretary Salvador Medialdea has formally informed SSS chairman Amado Valdez and commissioner Jose Gabriel La Vina that they would no longer serve in the state-run pension fund office.

"It's expiration of term and no renewal," Roque said, noting that the term of the two officials expired on June 13, 2017.

"Upon instruction of the President, your service in the SSS is hereby discontinued effective immediately," Roque said.

He said Duterte was just exercising his presidential prerogative.

Roque said Valdez and La Vina have been since serving the agency in a holdover capacity.

Duterte has yet to name their replacements. Celerina Monte/DMS