The Philippine president says he may not be able to survive his six-year term and seems overwhelmed by the immensity of his work, including the drug menace he's trying to fight.

President Rodrigo Duterte outlined in a rambling speech late Friday the obstacles he confronts in his deadly crackdown on illegal drugs, the heavy workload of the presidency and his cloistered existence now, saying "it gets to be a very lonely life."

Duterte said: "Will I survive the six years? I'd make a prediction, maybe not."

Duterte, who took office in June, did not explain what he meant but said there were people who want him removed, citing his reaching out to China and his lashing out at America after it raised concerns over his anti-drug crackdown.