Amazon saw sales growth in the UK slow last year, rising to just $7.29 billion (£4.47billion) from $6.48 billion in 2012, an uplift of just over half the 21% growth seen between 2011 and 2012.

Nick Bubb, an independent retail analyst, said he was surprised by the extent of the slowdown. "It's a bit below the growth you might expect. I'd have looked for more like 20%," he said. "But it's hard to keep growing at high double-digits and it's still a big number. I'm sure Jeff Bezos [the Amazon chief executive] is laughing all the way to the bank."