French judges say they have dropped an investigation into claims Palestinian leader Yasser Arafat was poisoned, according to BBC News.

Arafat died in Paris in 2004, aged 75. His wife says he was poisoned, possibly by highly radioactive polonium. The claims were seemingly backed up by tests carried out in Switzerland.

But a statement by prosecutors in Nanterre, near Paris, said polonium poisoning had "not been demonstrated" and that they would not continue their inquiries.

Arafat was diagnosed with a serious blood disorder and died of a stroke on 8 November 2004. But no post-mortem examination was carried out as his widow Suha did not ask for one.

In 2012, an investigation by al-Jazeera TV, in conjunction with Swiss analysts in Lausanne, found abnormal levels of polonium-210 on his personal effects. Suha Arafat then called for her late husband's body to be exhumed.

Three teams of French, Swiss and Russian investigators were allowed to take samples from Arafat's tomb in Ramallah.

But, earlier this year, one French prosecutor said the polonium samples were of an environmental nature.

"We'll continue our investigation to reach the killer of Arafat, until we know how Arafat was killed," Tawfiq Tirawi, the head of the Palestinian Authority's inquiry, told the AFP agency.