One Direction's Niall Horan has expressed his surprise at the success of his band's latest album.

The group released their third record 'Midnight Memories' on November 25 and it has performed well in charts worldwide.

It became the year's fastest selling album in the UK, whilst it is expected to be confirmed the band's third No.1 record in a row in the US.

Speaking on Twitter, Horan admitted:

"The reaction to midnight memories is mind blowing! I literally cannot believe the charts this week! You guys are unbelievable!"

A band's third album is often seen as a turning point due to the public possibly losing interest, but it seems 'Midnight Memories' is on course to become One Direction's biggest record yet.

Its first-week UK sales figures of over 237,000 units easily trumped their previous results, with 2012's 'Take Me Home' shifting 155,000 copies and 2011's 'Up All Night' selling 138,631.