Philippine president Rodrigo Duterte has warned he will declare a revolutionary government and arrest all his critics if a plot to oust him escalates.

"I will not hesitate to declare a revolutionary government until the end of my term and I will arrest all of you and we can go to a full scale war against the Reds," he said.

Army troops fire Howitzer to welcome President Rodrigo Duterte at a ceremony in Fort Bonifacio in suburban Taguig city east of Manila, Philippines earlier this month. Credit:AP

For days senior officials and Mr Duterte's administration have been warning of a plot to overthrow the mercurial president whose war on drugs has left more than 10,000 mostly poor Filipinos dead in the largest loss of civilian lives in Asia since the 1970s.

Armed forces chief Restituto Padilla said last week that Maoist rebels and lawless armed groups in the southern Philippines have initiated destabilisation moves against 72 year-old Mr Durtere, a former provincial mayor.