"Nag-resign na ako bilang president ng LMP (I have resigned as LMP president)," Estrada said in an interview. "Im useless as its leader. I do not have connections anymore."
The San Juan mayor, eldest son of ousted President Joseph Estrada and former First Lady Luisa Ejercito, said he relayed a verbal resignation to the LMP board on Jan. 21, a day after the first family left Malacañang.
The younger Estrada admitted that he was catapulted to the LMP presidency because of his fathers influence.
"Being the Presidents son, I was regularly approached by LMP members, who would ask me for help in the release of funds for projects in their towns and cities," he said.
The San Juan mayor was unanimously elected to lead the LMP in 1998, the same year his father became the 13th president of the Republic.
He admitted that with the new administration under President Arroyo, it would be difficult for the LMP to get funding.
But unlike his father who was abandoned by his Cabinet and military, the San Juan mayor still enjoys the backing of a majority of LMP members.
"The dilemma is that they do not want me to go," the young Estrada said.
The LMP is set to convene anew on Feb. 1 at the Sheraton Hotel in Makati City to discuss his resignation.
The mayor said he has not talked with or even seen the new President, whom his father has insisted is in office only in an acting capacity.
He is serving his third and final term as San Juans chief executive, and is eyeing the municipalitys lone congressional seat in the May polls.