Britney Spears experimented with cannabis when she was 17.

Britney Spears

Britney Spears

The 34-year-old singer admits she smoked the drug during her teenage years and while she no longer does it, she still gets "contact high" by inhaling the fumes from fans who smoke marijuana at her Las Vegas residency show.

Speaking on the 'Jonathan Ross Show', she said: "I am aware of the partying that's going on. A lot of the people are very intoxicated during the shows... I actually got contact high. I haven't smoked weed since I was like 17 years old and all of a sudden, towards the end of the show, it was so strong I couldn't function because I just got the contact of it. I was like 'Oh my goodness!' I had to leave, I had to go. I kinda just said, 'I can't do it anymore.'"

The star performed in The Roundhouse in London for Apple Music Festival on Tuesday night (26.09.16) and admitted she enjoyed the experience far more because the crowd weren't "high".

She said: "I performed and the audience... they were right there in front of you and it was so much more personal and they weren't drunk or high, it was so intimate they were so present and there with me so it was really nice."

Britney suffered an infamous meltdown in 2007, which saw her shave her head and attack a paparazzi's car with an umbrella leading to her entering rehab to recover.

But the 'Make Me' hitmaker star got her act together and as well as storming the music scene with her latest album, she's a proud mum to her two sons Sean, 11, and Jayden, 10.

Speaking about wanting to instil "wisdom" in the boys - whose father is her ex-husband Kevin Federline - she said: "I just want them to be strong men and I want them to have strength and I hope that I give them wisdom and just be a good mother for them."