JFK’s rosary beads are expected to sell for up to $400,000 at Christie’s on June 15.

The set consists of a sterling silver cross engraved “John F. Kennedy” and a chain made up of black onyx beads.

The rosary is sterling silver and engraved 'John F. Kennedy'

Kennedy gave this set to his friend and confidante David Powers (1912-1988) sometime in the early 1960s.

Both men were Catholics and regularly attended mass together.

They met in 1946, when Kennedy knocked on the door of Powers’ apartment building in Boston looking for help running his senate campaign.

Powers was unemployed at the time, having just returned home from the war.

In a 1983 interview with the New York Times he explained: ''One night I was sitting home baby-sitting the eight children of my widowed sister.

“There was a knock on the door and I answered.

"The light must have been 15 watts to save on expenses, and in the semi-darkness I could see this tall, thin handsome fellow, and he reached out his hand and said: 'I am a candidate for Congress. Will you help me?'”

The two men went on to forge a lasting friendship. Powers followed Kennedy all the way to the White House.

Powers was riding one car behind Kennedy when the president was killed in 1963.

In April, Kennedy’s 1945 diary sold for a record $898,500.

We have this genuine JFK 1960 campaign poster for sale.

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