A solid gold, diamond-encrusted model of the iPhone 5 has been named the world's "most expensive smartphone," Digital Spy said.

The £10-million iPhone 5 Black Diamond, made by British designer Stuart Hughes, was commissioned by an unnamed Chinese businessman for use as his regular phone.

The device's case is made from gold, with a black single deep-cut diamond serving as its home button and a screen made from Sapphire glass.

Hughes has adorned the Apple logo with 53 flawless diamonds, and the back cover is encrusted with the precious stones.

The designer is taking commissions for additional models of the iPhone 5 Black Diamond, and offers a range of other luxury gadgets via his website Goldstriker.