A group of cross-party MPs who've been on a fact-finding trip to Canada predict the UK will fully legalise cannabis use within five to ten years.

Canada became the first G7 country to allow recreational use of the drug in 2018.

Of the three politicians in the group one had a significant shift in his position.

Labour's David Lammy now backs legalisation, against his party's official stance.

Mr Lammy, alongside Conservative Jonathan Djanogly and Liberal Democrat Sir Norman Lamb were all filmed on their journey for a Radio 1 Newsbeat documentary called Legalising Weed: Canada's Story.

Media playback is unsupported on your device Media caption Legalising Weed: Canada's Story

Currently cannabis is designated as a Class B drug in the UK and anyone caught with it could face up to five years in prison.

However, there has been a shift in approach towards medicinal cannabis products, which can now be legally prescribed to some patients.

The decision to relax those rules followed an outcry over two boys with severe epilepsy being denied access to cannabis oil.

It's argued that where cannabis has been legalised for medical use, authorised recreational use often follows.

Image caption Tottenham MP David Lammy visits a legally-grown cannabis crop in Canada

"I want the market legalised, regulated and taken away from crime gangs," said Tottenham MP David Lammy after returning from visiting Toronto.

"For young people not to be criminalised by use and properly educated.

"I want to see the strength of the stuff reduced, labelled and properly organised in this country."

The Liberal Democrat Party already officially backs legalising cannabis in the UK.

MP for North Norfolk, Sir Norman Lamb led that policy decision.

Whilst in Canada he wanted to legally sample cannabis oil to try to help him sleep.

But he was very aware that such a product would be illegal in the UK.

He may be the only serving British MP to ever openly take a cannabis product on camera.

"Taking this oil is purely for sleeping for relaxation, I will take it before bed and before my flight home."

It's different to the cannabis oils available legitimately in the UK because it contained THC, the compound that gets users high.

"I was really anxious because I was chairing the technology and science select committee and I was travelling back over night, and I thought if I get back with no sleep it will be a challenge."

He said he did not feel high but it did help him fall asleep.

"I slept incredibly well.

"I took the drops and I slept very well on the plane home, I actually slept through breakfast."

The trip was organised by a UK-based campaign group, Volte Face, which wants the UK to legalise the drug.

It's part sponsored by a big North American cannabis company called MPX.

Newsbeat suggested that it was trying to use its money to influence British politicians.

Image caption Scott Boyes says his company wants to make profit out of selling cannabis responsibly in the UK

"We're moving it away from organised crime to a legitimate commercial industry," Scott Boyes, MPX CEO, told us.

"We've had a lot of UK investors invest in our company and we're moving into six countries.

"A lot of the money we have raised has come out of the UK, so I don't consider it interfering with other people's politics and a lot of the expenses have been born by themselves."

Sir Norman Lamb and David Lammy decided to fund their own flights and accommodation.

But the MPs also realise Canada's experience has not been without problems. In the documentary we hear from Piper Courtenay whose title is Cannabis Editor for a weekly newspaper.

She describes how technically illegal, but often described as "grey", cannabis providers still thrive.

The limits on fully licensed products mean there's still a market for things like edibles and other cannabis products.

Around half of the cannabis bought in Canada still comes from illegal sources.

"It's certainly better than the legal product I have tried so far, because they genuinely care about growing good craft cannabis," she tells us.

Image caption Products on sale at a legal shop in Canada

All three MPs on the trip believed that the UK would follow Canada's lead and legalise cannabis for recreational use in the next decade.

But Conservative MP for Huntingdon, Jonathan Djanogly, was perhaps unsurprisingly given his party name, the most conservative with his predictions.

"I think we have got a lot to learn before the legalisation of recreational cannabis, which I think will happen at some point," Jonathan Djanogly told us.

"I think we're on a 10 to 15 year cycle which would mirror what has happened in Canada."

The other MPs felt it would happen sooner and closer to five years.

However, the government told Newsbeat it "has no intention of changing the law" when it comes to legalisation.

A Home Office spokesman said: "The legalisation of these substances would not eliminate the crime committed by the illicit trade, nor would it address the harms associated with drug dependence and the misery they can cause to families and society."

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