LONDON - British singer Robbie Williams said on Saturday he was not engaged to his girlfriend, Ayda Field -- despite "proposing" to her a day earlier.

The pop star popped the question to Field, 30, live on Australian radio on Friday, only for his London-based spokesman to say it was a joke and deny they were engaged.

Adding to the confusion, Williams' mother Jan later told British radio that her 35-year-old son intended to marry Field "in the not-too-distant future."

On his website, Williams posted a brief blog under the headline "Robbie And Ayda: Are They Or Aren't They?"

It read: "Hey all. We are not engaged. rob x"

One of Europe's most successful entertainers, Williams rose to fame as a member of the hit boy band Take That before forging a successful solo career.

The singer, who now lives in Los Angeles, has been out of the public eye since he left a U.S. rehabilitation center in March 2007 where he was treated for prescription drug addiction.

His new album "Reality Killed the Video Star" is his first release in three years.

(Reporting by Mike Collett-White, editing by Mark Trevelyan)