London, Apr 10 (ANI): Despite having a history full of drug and alcohol abuse, Britney Spears recently walked off stage only because she made to feel uncomfortable by fans smoking marijuana during one of her 'Circus' gig.

The 'Toxic' hit-maker stormed off after three songs, and did not return for 40 minutes at Vancouver's GM Place, Canada.

A loudspeaker announcement was later made, sternly asking the 19,000-strong audience to extinguish all their smokes if they wanted Britney to return.

Baffled gig-goers booed the star in chorus, while it was claimed that pot smoke had been detected around the stage, which made it "unsafe" for the star to perform.

Britney finally returned to a huge applause, but ended the two-hour show with a rather odd message.

"Thanks Vancouver, you were wonderful. Drive safe. Don't smoke weed," the Sun quoted her as telling the audience.

While Britney has battled mental health problems in the past, her mom Lynne, 54, has said that the pop princess began experimenting with drugs aged 15.

At the age of 16, she was caught with cocaine and marijuana on a private jet.

"Everyone was really confused when she walked off so early on, especially with her track record for going off the rails," a source said.

"Britney was furious backstage, claiming smoke from cigarettes and joints was making it impossible to perform.

"Telling the crowd not to smoke weed after she kept them waiting for so long wasn't her best move," the source added.

The 27-year-old star's representatives said that the gig came to a halt midway as crewmembers became sick because of the smoke. (ANI)