Poe has been endorsed by lots of fans - but no political party yet

A political newcomer, the action film star said he was not motivated by personal ambition, but rather was giving in to public pressure.

"I cannot turn my back," he told supporters in Manila on Wednesday.

His announcement means the 64-year-old actor could face incumbent President Gloria Arroyo, who has also said she is running.

Fernando Poe Jr is close to former President Joseph Estrada - another actor turned politician who was forced from power by massive protests in 2001.

There comes a time when a man faces the hardest decision of his life and this time has come to me now Fernando Poe

Mr Poe commands a huge following - especially among poorer Filipinos.

Opinion polls have suggested he would be one of the leading candidates if he were to run.

"There comes a time when a man faces the hardest decision of his life and this time has come to me now," he said.

No political party had yet endorsed him.

Fernando Poe conceded that he would have to go through the selection process of the main opposition party, adding: "If they adopt me, why not?"