The Amazon.co.uk MP3 store is offering 100 top-selling tracks for 29 pence (42 cents), reduced from 59 pence (86 cents), to coincide with the launch of variable pricing on the iTunes store in the U.K.

The iTunes pricing in the U.K. now varies between 59 pence, 79 pence ($1.16) and 99 pence ($1.46); most tracks used to cost 79 pence.

Amazon.co.uk launched a similar promotion last month on ten tracks.

Following its launch in December, the service now has 5 million tracks available, having added over 10,000 tracks a day to its catalog.

"Our aim is to always offer the lowest prices and the most comprehensive choice,' said Julian Monaghan, head of music buying at Amazon.co.uk, in a statement. "Since our launch just four months ago, we have been presenting our customers with some great deals on MP3s whilst rapidly expanding our catalog and we will continue to do so going forward."

The promotion includes tracks by Lady Gaga, Flo Rida, Lily Allen, Take That and the Prodigy.