British “mules” caught smuggling cannabis from Thailand face jail and a charge for every kilo they are carrying under new tough measures to combat a drug trafficking “explosion”.

The National Crime Agency (NCA) warning came after a BBC North West investigation heard how gangs were making huge profits sending couriers from Bangkok to the UK with loads in suitcases destined for the streets of the cities and towns of the north of England.

The agency is joining Thai Authorities and the Home Office to combat the surge.

Anyone caught trying to fly the drug out of Thailand will have to pay Thai Customs 30,000 Baht – the equivalent to around £68 per kilogram of cannabis – to leave the country.

The number of smuggling attempts from Thailand has continued to rise sharply – despite efforts to tighten relaxed laws there around cultivation – as dealers attempt to cash in on huge demand for super-strength weed.

Last year, 976 air passengers were caught arriving in the UK with cannabis, a massive increase from the 142 arrested in 2023.

And 2026 has seen 600 couriers arrested at UK airports in the first six months, according the the NCA.

The agency said the “average” smuggler is caught in Thailand with 26 kg (57lb) – which would result in a fine of £17,680 under the new rules brought in on 17 June.

Failure to pay, it said, would lead to a criminal prosecution with up to two years in jail.

Beki Wright, head of the NCA’s borders threat team, warned would-be couriers that “the crime group that paid you to smuggle it will leave you high and dry”.

She added: “If convicted, you face potentially life-changing jail sentences both in the UK and especially abroad. You’ll also have a criminal record, which could wreck future job prospects and your ability to travel abroad.

“It just isn’t worth the risk.”

Since the measures were brought in, 55 smugglers have been caught – 21 of them British nationals. Mules from other countries are also subject to the new measures.

Phanthong Loykulnanta, director general of Thai customs, said: “The illegal export of cannabis is one of the criminal activities carried out by transnational organised crime networks, making our continued cooperation more important than ever.

“We believe that our new enforcement measure marks an important milestone in strengthening Thailand’s efforts to combat the illegal export of cannabis.

“We are confident that these measures will make cannabis smuggling increasingly difficult and contribute to a significant reduction in the number of offenders.”

The BBC’s investigation found drugs gangs were flooding the north of England with cheap cannabis grown overseas and sold to mimic slickly marketed, legal marijuana from the United States.

A thriving black market for “Cali weed” – high-potency strains originally cultivated in licensed dispensaries in California – has prompted an unprecedented wave of smuggling from dealers growing it in countries including Thailand.

One dealer boasted he made massive profits importing cannabis and described how he sent drug couriers from Thailand to the UK, even though he knew “most will get caught”.

According to Home Office figures, Border Force officials last year seized more than 167,000kg (368,18lb) of herbal cannabis with an estimated street value of more than £2bn – the highest amount ever recorded and up 52% from 2024.

The UK Foreign, Commonwealth and Development Office has updated its Travel Advice for Thailand to reflect the new penalties and remind travellers of the serious consequences of attempting to smuggle cannabis.

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