RAMALLAH  - Israel poisoned the late Yasser Arafat with the lethal radioactive substance polonium, a nephew of the veteran Palestinian leader alleged on Thursday, prompting an Israeli denial. “We accuse Israel of killing Yasser Arafat by poisoning him with that lethal substance,” Nasser al-Qidwa told AFP. “Those responsible for that assassination should be held accountable and judged,” said Qidwa, who is also president of the Yasser Arafat Foundation. Allegations that the leader was poisoned were resurrected earlier this month after Al-Jazeera news channel broadcast an investigation in which experts said they had found high levels of polonium on his personal effects. Polonium is a highly toxic substance which is rarely found outside military and scientific circles, and was used to kill former Russian spy turned Kremlin critic Alexander Litvinenko, who died in 2006 shortly after drinking tea laced with the poison.But a spokesman for Israeli Prime Minister Benjamin Netanyahu completely rejected Qidwa’s charge, denying any involvement in the 75-year-old’s death.“Israel was not involved in the death of Arafat,” Netanyahu’s spokesman Mark Regev told AFP. “All the medical files are in the hands of the Palestinians and it was not Israel who is preventing their publication.”