Rare colour photos taken of The Beatles during their first ever U.S. tour are set to go under the hammer in the U.K. in March (13).

Sixty-five slides taken by famed late physicist Dr. Robert Beck include shots of the Fab Four both onstage and off as John Lennon, Paul MCCartney, George Harrison and Ringo Starr played a string of sold-out gigs in August, 1964, shortly after making their iconic appearance on America's The Ed Sullivan Show that February (64).

One of the images shows Harrison playing his red Rickenbacker guitar, which featured in the band's film A Hard Day's Night.

The collection of pictures will be sold at auction on 22 March (13), exactly 50 years after the release of The Beatles' debut album, Please Please Me.

Omega Auctions boss Paul Fairweather tells the Bbc, "This is a fabulous collection, particularly given that all the slides are in colour."

The transparencies and copyright for the shots will be sold together, and they are expected to fetch as much as $24,000 (£15,000).