British pop star Lily Allen, who was around six months pregnant, has lost her baby, her spokesman said on Monday.

The 25-year-old singer previously had a miscarriage when she was dating Chemical Brothers star Ed Simons in 2008.

"It is with great sadness that we have to confirm that Lily Allen and Sam Cooper have lost their baby," her spokesman said in a statement.

"The couple ask that their privacy be respected and that they be left alone at this deeply distressing time. No further comment will be made."