The cup came from a Presley concert six months before he died

The few tablespoons came from a plastic cup Presley sipped at a concert in North Carolina in 1977 - which was kept by fan Wade Jones, who was then 13.

He saw Presley drink from it and a guard gave it to him as a souvenir.

He kept the water in a freezer until 1985, when it was put in a sealed vial. But he is refusing to sell the cup.

I promise this thing is 100% legitimate Wade Jones

Mr Jones is willing to put the Styrofoam cup on display, possibly to coincide with Presley's birthday on 8 January - for a minimum of $300 (�156) plus travel expenses.

Presley drank from the cup on stage while introducing his band at the concert at Greensboro, Mr Jones, now 40, said.

He decided to auction the water after a grilled cheese sandwich with an image resembling the Virgin Mary fetched $28,000 (�14,500) on eBay.