Elvis Presley's ex-wife Priscilla has claimed the King knowingly took his own life when he died from a drug-related heart attack.

The 72-year-old made the admission ahead of the premiere of the new HBO documentary, Elvis Presley: The Searcher, which looks into the singer’s connection to Memphis, Tennessee.

In the programme, which is due to air on Saturday, Priscilla opens up about the depths of addiction of her late ex-husband.

She said he “knew what he was doing”.

Priscilla said she and loved ones had failed to try to wean him off drugs but his determination was strong and influence was overpowering.

(Image: ITV)

(Image: Michael Ochs Archives)

She says: "He knew what he was doing and people go, 'why didn't anyone do anything?' Well, that's not true.

“People there in the inner group did - but you did not tell Elvis what to do. You'd have been out of there faster than a scratched cat. They would try and - no way."

The bombshell revelation comes just four months after the discovery of two suicide notes purportedly written by the King.

(Image: Getty Images Europe)

Family members say they prove he intended to take his own life by swallowing huge overdoses of prescription painkillers.

In recently discovered notes to his friend and road manager Joe Esposito Elvis wrote: "I'm sick and tired of my life" and "I need a long rest".

(Image: Getty)

(Image: Rex)

His stepbrother Rick Stanley said: "To me, it's a clear indication that suicide was on his mind."

Priscilla divorced Elvis in 1973 after the birth of their only child, Lisa Marie, but they remained close until his death four years later at the age of 42.

She blames his deadly drug habit on his time in the US military when he was based in Germany.

"They gave them to the soldiers over there to keep them awake," she says.

(Image: ITV)

(Image: Michael Ochs Archives)

"He had manoeuvres that he had to do late at night, so the pills were given to the guys and that's how he started.

"And if you take a sleeping pill, you have to do something to get yourself awake. He was in uncharted territory, he truly was, and he did this and tried to do this alone."

Following Elvis's death, it was found one doctor alone had prescribed him more than 10,000 pills in eight months.

His weight had also ballooned to more than 18 stone as a result of binge eating.

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