The president of the Philippines is a “highly impulsive individual who has difficulty controlling his urges and emotions” and suffers from a long-term psychological condition, according to a rediscovered assessment of his mental health.

A psychological report on Rodrigo Duterte was commissioned by Dr Natividad Dayan during the annulment of his marriage to ex-wife Elizabeth Zimmerman in July 1998, when Mr Duterte was mayor of Davao City.

The assessment found Mr Duterte suffered from “antisocial narcissistic personality disorder”, a pattern of abnormal behaviour characterised by "gross indifference, insensitivity and self-centeredness" and "grandiose sense of self-entitlement and manipulative behaviours".

The politician was described as having a “pervasive tendency to demean, humiliate others and violate their rights and feelings”, and was “unable to reflect on the consequences of his actions.”

He was found to readily engage in “unhealthy and destructive behaviours” and had “poor capacity for objective judgement”, failing to “see things in the light of facts”.

Mr Duterte recently made headlines for launching expletive-laden attacks against the EU and US president Barack Obama, as thousands continue to be killed without trial as part of the leader’s war on illegal drugs.

Court papers from the trial showed Dr Dayan concluded Mr Duterte was “psychologically incapacitated to handle essential marital obligations”, due to his “inability for loyalty and commitment” and “lack of capacity for remorse and guilt".

During the court case, lawyers also spoke of Mr Duterte’s “womanising” ways and detailed claims of numerous affairs he was involved in while married to Ms Zimmerman.

The most controversial quotes from Rodrigo Duterte Show all 9 1 /9 The most controversial quotes from Rodrigo Duterte The most controversial quotes from Rodrigo Duterte On killing drug addicts “These sons of whores are destroying our children. I warn you, don’t go into that, even if you’re a policeman, because I will really kill you. If you know of any addicts, go ahead and kill them yourself as getting their parents to do it would be too painful” The most controversial quotes from Rodrigo Duterte Message to China “I will go there on my own with a Jet Ski, bringing along with me a [Phillipino] flag and a pole, and once I disembark, I will plant the flag on the runway and tell the Chinese authorities, ‘Kill me’ ” AP The most controversial quotes from Rodrigo Duterte Christmas message to law-breakers “If you do not want to stop, and just continue committing crimes, then this would be your last Merry Christmas” AP The most controversial quotes from Rodrigo Duterte On sex life “I was separated from my wife. I’m not impotent. What am I supposed to do? Let this hang forever? When I take Viagra, it stands up” AFP/Getty Images The most controversial quotes from Rodrigo Duterte On the drugs trade “None of my children are into illegal drugs. But my order is, even if it is a member of my family, ‘kill him'" AP The most controversial quotes from Rodrigo Duterte Insulting the Pope “We were affected by the traffic. It took us five hours. I asked why, they said it was closed. I asked who is coming. They answered, the pope. I wanted to call him: ‘Pope, son of a wh**e, go home. Do not visit us again’” AFP/Getty Images The most controversial quotes from Rodrigo Duterte Joke about rape “I saw her face and I thought, 'What a pity... they raped her, they all lined up. I was mad she was raped but she was so beautiful. I thought, the mayor should have been first” AFP/Getty The most controversial quotes from Rodrigo Duterte Insulting Barack Obama "Mr Obama should be respectful and refrain from throwing questions at me about the killings, or son of a bitch, I will swear at you in that forum" REUTERS The most controversial quotes from Rodrigo Duterte On Abu Sayyaf Islamic militants "If I have to face them, you know I can eat humans. I will really open up your body. Just give me vinegar and salt, and I will eat you. If you annoy me to the fullest... I will eat you alive. Raw" EPA

In her testimony, Ms Zimmerman described her marriage to Duterte as “miserable and unhappy” and criticised his volatile temper, according to ABS-CBN News.

Filipino actress Agot Isidro recently launched an angry online tirade against Mr Duterte, describing him as a "psychopath" and telling him to "get checked".

More than 3,600 people have been killed in Mr Duterte’s first 100 days in office as part of his brutal crackdown on drugs, human rights experts have estimated.

The president recently said his extrajudicial crackdown on drug dealers and criminals will continue because he “cannot kill them all”.