Arafat, a guerrilla leader who became the first Palestinian president, died in 2004 from a sudden illness contracted while under an Israeli siege at his Ramallah headquarters in the occupied West Bank.
Many Palestinians have long believed Israel killed him - a charge Israel denies - but an official Palestinian Authority investigation headed by Tawfiq Tirawi has yet to produce any evidence.
"I promise that the next press conference will be the last, and will cast into the light of day everyone who perpetrated, took part in or conspired in the matter," Tirawi told Palestine Today television.
"We are in the last 15 minutes of the investigation," he added.
A Swiss forensic lab said in November that Arafat's bones contained unnaturally high amounts of rare and deadly radioactive isotope, polonium which it said "moderately supported" a contention he was poisoned.
A report by the British Lancet, one of the world’s leading medical journals, in October also supported earlier findings that Arafat was poisoned to death nearly a decade ago.
The decision to exhume Arafat’s body was made after French prosecutors opened a murder probe into his death in August 2012 following the discovery of high levels of polonium on his personal belongings.
SHI/SHI