Ed Sheeran has quit smoking marijuana because he prefers to be "alert".

The singer, who wrote song Sweet Mary Jane about his love of the drug in 2015, has now told reporters at The Daily Star that he has given up his smoking sessions as he found that the psychoactive substance clouded his creativity.

"I've stopped smoking weed," he said. "I found myself just sitting at home watching films. I only ever create (when I'm) sober - I like to be alert. I find most ideas happen when you have a cup of tea. For me, anyway."

Ed went on to explain that he has also decided to ditch alcohol until his live concerts are over.

"We don't have booze in the venue until after the gig" the 27-year-old shared. "I love embracing chaos, but only when the job's done. I worked really hard to get into this position - and I'm going to continue working hard to maintain that position and grow."

Since breaking into the music industry with track The A Team in 2011, Ed has become one of the most successful names in the business - writing hit after hit for himself and other stars.

And as well as his knack for writing chart-topping songs, Ed has become known worldwide for his ginger hair - and is thrilled he's had input in changing the stigma surrounding redheads.

"Parents with children with ginger hair come up to me and go, 'It's cool to have ginger hair,'" he laughed. "I was ribbed about it at school, it was the thing that got me noticed. Now everyone loves (Prince) Harry and (Harry Potter star) Rupert Grint. Ladies love Grint."