The daughters of the late Blues legend BB King have sensationally claimed that he was poisoned.

The iconic performer, best known for hits, such as Lucille, Sweet Black Angel and Rock Me Baby, passed away at his home in Las Vegas on 14 May. He was aged 89.

E Online reported that in the wake of his death his daughters Patty King and Karen Williams filed affidavits alleging that he was murdered.

Both women accuse LaVerne Toney, King's business manager, and Myron Johnson, his personal assistant, of neglect and claim that although the associates are medically unlicensed, they were seen administering medications, fluids and substances to the star.

"I believe my father was poisoned and that he was administered foreign substances to induce his premature death," they said in their affidavits. "I believe my father was murdered."

"(I) request a formal investigation into this matter," the court documents reportedly added.

Although the coroner's report stated that there was "no evidence to substantiate the allegations," the siblings have since requested a toxicology analysis or autopsy be conducted to determine the cause of their father's death.

In April, King, who had been diabetic for almost 20 years, was admitted to a Las Vegas hospital for dehydration resulting from Type II diabetes.

King and Williams allege that "King was sequestered from all family members" in the days leading to his death, and that Toney, who is the executor of King's estate, and Johnson were the only people with him.

But an attorney for King's estate dismissed their accusations as "ridiculous".

"I hope they have a factual basis that they can demonstrate for their defamatory and libelous allegations," Brent Bryson said in a statement.

Toney, who recently shrugged off the allegations, saying "What's new?" previously paid tribute to his late client.

"King is where he wishes to be. He's always told me he doesn't want to be in a hospital. He wants to be at home," he said.