Palestinian Authority President Mahmoud Abbas has invited Swiss experts who investigated the death of Yasser Arafat to probe the deceased leader’s body, a senior Palestinian official said Friday.

Chief Palestinian negotiator Saeb Erakat told AFP late Sunday night that Abbas had requested the experts’ presence in Ramallah immediately to take samples.

Abbas has stepped up calls for an investigation into Arafat’s 2004 death, asking French leader Francoise Hollande to form an international commission.

Palestinian officials have reopened the case of Arafat’s unexplained death in a Paris hospital after Al Jazeera aired a report last week pointing to signs that he may have been poisoned by radioactive substance polonium.

Abbas asked Hollande to form the commission during a meeting between the two on Friday, the Palestinian news Agency Ma’an reported Sunday, quoting Palestinian negotiator Saeb Erekat. Abbas asked that the probe be modeled on the investigation into the assassination of former Lebanese prime minister Rafiq Hariri.

Erekat, who has joined calls for Arafat’s body to be exhumed, told Ma’an that Ramallah would seek to have the Arab League head up a joint Arab-International commission of inquiry.

“The truth about the martyrdom of Arafat must be revealed, as well as the tools used to kill him. The perpetrators must be put to justice,” Erekat told the agency.

Rumors swirled around Arafat’s death in 2004 after he was rushed from his compound in Ramallah to France suffering from a mystery illness. Analysis of Arafat’s clothing conducted by Al Jazeera a Swiss research institute found irregularly high levels of the rare radioactive element. Polonium’s effects on the human body are deadly but largely undocumented.

“Arafat’s personal effects, particularly those with bodily fluids on them, registered much higher levels of the element” than occurs naturally, Al Jazeera reported. “The urine stain on [Arafat’s] underwear” registered 27 times the amount of radioactivity than a control pair of underwear.

In an interview with Army Radio Thursday, Darcy Christen, the Swiss institute’s spokesman, said researchers were surprised by the high levels of polonium, but could not determine that it was the cause of Arafat’s death.

“The fact that we found polonium doesn’t mean it was there eight years ago,” said Christen, explaining that to determine that, the body itself needed to be checked.

Israel has derided the new poisoning claims. “All of a sudden, Suha’s checking her wash basket and discovered clothes that weren’t washed for eight years,” deputy foreign ministry spokesperson Paul Hirschson told Chinese news agency Xinhua. “Suddenly, out of nowhere a couple of garments turn up; we test them, and presto! There’s polonium.”

Stuart Winer contributed to this report.