Professor Roger Pertwee
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Call for licensed cannabis sales

Certain forms of cannabis should be considered for licensed sale, says Professor Roger Pertwee, one of the UK's leading researchers of the drug.

He is to make the call in a speech at the British Science Association festival in Birmingham.

Speaking to BBC Breakfast, Professor Pertwee says he has developed an 'extreme' scheme that would see certain forms of cannabis legalised and sold as a branded product.