RAMALLAH (Ma'an) -- The committee to investigate the death of Yasser Arafat is ready to take samples from the the president's body but is waiting for his family's approval, committee head Tawfiq Tirawi said Wednesday.

Arafat's widow Suha called for an autopsy after a Swiss Institute found "surprisingly" high levels of polonium-210 in the iconic leader's clothing following an examination for an Al Jazeera documentary that aired Tuesday.

Tirawi told Ma'an his committee had already discovered inconsistencies over the cause of Arafat's death but its continuous investigations, working under occupation, had limited capacities.

By specifying the substance, Al Jazeera's investigation simplified the committee's work, Tirawi said, as an autopsy could test levels of the poison to confirm the cause of death.

If the autopsy confirms Arafat was murdered, the committee will investigate who was responsible but the probe would take time, Tirawi said. Reaching accurate results is more important than concluding swiftly, he said, adding that the PLO, the PA and Fatah were ready to cooperate with any parties in an investigation.

Israel has long been seen by many Palestinians as the prime suspect behind the mysterious illness that killed the 75-year-old Arafat in 2004.

Avi Dichter, who headed Israel's Shin Bet intelligence service in 2004, denied involvement in a plot to poison Arafat's food, when asked by Israel's Army Radio on Wednesday.

"Yasser Arafat had many enemies, domestically, abroad. But let them investigate ... The Palestinians know well how to investigate what goes on in their house. Let them investigate and find out," Dichter said.

In 1997, Israeli assassins were caught trying to poison Hamas leader Khalid Mashaal in Jordan. Israel is also suspected in the 2010 death in a Dubai hotel room of a Hamas commander, Mahmoud al-Mabhouh, who UAE authorities said had been drugged.

Suha Arafat said determining there had been a plot to kill her husband "will glorify more his legacy" and harden Palestinian resolve in any future negotiations with Israel.

"Arafat wanted to arrive with the Palestinian cause to a Palestinian state, and because of this they got rid of him," she said, without elaborating.

Israel's foreign minister in 2004, Silvan Shalom, rejected at the time as "scandalous and false" the idea that his country had a role in Arafat's death. But Israel had earlier threatened Arafat, blaming him for Palestinian violence.

After losing 15 citizens to suicide bombings in September 2003, Israel's security cabinet decided to "remove" Arafat, without elaborating publicly on the precise action it planned to take. An Israeli newspaper quoted Dichter as saying at the time that it would be better to kill Arafat than exile him.

Reuters contributed to this report.