Prime Minister Ahmad Qureia said on Wednesday that the report, which was heavily based on the findings of French doctors who treated Arafat before his death in November, was unable to pinpoint a cause of death.
However, the document suggested that doctors might be able to give a precise reason in the future.
"The French and Palestinian doctors have concluded that there was no known cure for the illness that afflicted the president," Qureia, who wrote a foreword to the report, told journalists.
He said the death of the long-time Palestinian leader was not a result of "bacteria, nor a virus, a microbe, a cancerous tumour nor of Aids as has been said".
"Even the possibility of poisoning was examined, but no known poison has been detected," Qureia added.
"As a result, we should not close this file, for there could be medical developments in the future which could determine the cause of his death."
Arafat died on 11 November in a military hospital near Paris. He had been airlifted to France from his offices in the West Bank town of Ram Allah on 29 October and lapsed into a coma on 3 November from which he never emerged.
The report repeated previous assessments that Arafat's death "resulted from a severe haemorrhaging of the brain".
Conspiracy theories surround the
death of Arafat late last year
But it added that Arafat's "clinical state presented several symptoms which could not be explained in the framework of nosology" (the study of diseases).
Mystery over the cause of 75-year-old Arafat's death has for months been subject to conspiracy theories, chiefly that he was poisoned by long-time foe Israel, in part fueled by allegations from some Palestinian officials.
A report by The New York Times last month, based on the French medical report, said Arafat had died from an unidentified infection that was "highly unlikely" to have been caused by Aids or poisoning.
A new book by two Israeli journalists has claimed that there are three possible causes of death: infection from a germ that poisoned the blood, Aids or poisoning.
Faruq Qaddumi, who succeeded Arafat as the head of the main governing Fatah faction, has insisted that Arafat was poisoned.
"The poison was administered in the food and in the medication he swallowed," the Tunis-based Qaddumi told reporters in July.