N-Dubz rapper Dappy has apologised after he was filmed taking the drug mephedrone.

The footage, obtained by The Sun newspaper, was apparently shot after a gig in Essex last month.

At the time, the substance - also known as meow meow - was legal, but it has since been classified a Class B drug.

Speaking to the newspaper, Dappy said: "I was taking meow meow. I was on a night out with mates and it got a bit rowdy.

"Meow meow was legal then and lots of my mates were taking it too. I know this drug has now been made illegal and would not endorse any of our fans taking it."

And appearing on GMTV this morning, the rapper said he had “learned my mistake and I will never do such things again”.

The incident comes just two months after Dappy was forced to apologise for sending abusive text messages to a fan.

Members of N-Dubz, including Dappy, were also criticised earlier this month for firing paintballs at fans from their tour bus.

(by Jason Gregory)