MANILA, Philippines -- Environmentalist Nicanor Perlas filed his certificate of candidacy for president at the Commission on Elections central office in Manila on Sunday afternoon, and vowed to lead the country away from the "politics of impunity."

Perlas was accompanied by his son Christopher Michael in filing his CoC in an already crowded race. He cited last week's massacre in Maguindanao, in pledging to create the political environment conducive for "authentic choices" and change for Filipinos.

He said Filipinos "are so tired of choosing between lesser evils and greater evils" during the elections and "want real change and authentic choices."

Perlas, 59, said that aside from P2 million in personal funds, he would rely on volunteers for his campaign.

He admitted he had yet to pick his vice presidential candidate and his senatorial slate as of Sunday., adding that his standards for "new politics" have proven "too high" for the many candidates whom he said have been concerned only about winning.

He said his platform would focus on poverty eradication, moral and effective governance, social justice, comprehensive education reform and visionary initiatives.