The group have premiered 'Beautiful World', which features as one of four new tracks on their forthcoming Greatest Hits collection.
The song was co-written by band member Mark Feehily along with Ruth-Anne Cunningham and John Shanks.
The other new cuts on the LP include current single 'Lighthouse', which was written by Gary Barlow, 'Wide Open' and 'Last Mile of the Way'.
As well as the new material, Westlife have included 14 of their hits including debut single 'Swear It Again', fan favourite 'Flying Without Wings' and charity release 'Uptown Girl'.
The group recently added nine extra dates to their 2012 farewell tour after experiencing phenomenal demand for the initial run of concerts.
Westlife's new single 'Lighthouse' is available to download now, while their Greatest Hits collection will be released on November 21.
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Listen to Westlife's 'Beautiful World' below: