Coldplay unveiled a new song during some shows on its recently completed South American tour, according to NME.com. At a gig in Buenos Aires, Argentina, the British quartet played a never-before-heard track called "Don Quixote," with singer Chris Martin telling the audience, "We felt like it would be good for us if we had a special song that celebrated how much we think of the Latin American audiences . . . We decided to write a song about the magic escape that the band receives when we come to Latin America -- this is called 'Don Quixote.'"

The song was said to be primarily based around acoustic guitar and thought to be the product of recording sessions for the group's fifth album.

Martin recently told a Brazilian TV program that the band hopes to release its next record in time for Christmas of this year.

Coldplay has been working on its new album with producer Brian Eno, who also teamed with the band on 2008's hugely successful Viva La Vida, Or Death And All His Friends.