The mother of a severely epileptic boy has called for a meeting with cabinet ministers to discuss re-thinking “massively outdated” laws on medical marijuana so other children can receive treatment.

Charlotte Caldwell also said on Sunday she wanted them to assure her she would not face “another battle” for 12-year-old Billy when the 20-day supply returned by the Home Office runs out.

The Government’s initial refusal, and then its change in stance, has prompted renewed debate on legislation, with a Conservative MP who leads a drug policy parliamentary group saying existing laws are “frankly absurd”.

After a week-long struggle, Home Secretary Sajid Javid used “an exceptional power” on Saturday to return some of the medicine confiscated from the mother when she tried to bring it into the UK from Canada.

Ms Caldwell, 50, said: “I want nobody in Government, and nobody who has been impacted by massively outdated laws, to be under any impression that this is job done. This is just the start.

Charlotte and Billy Caldwell
Charlotte Caldwell says Britain is ‘stuck in the 1970s’ in its attitude to drug policy (Yui Mok/PA)

“I want to meet the Home Secretary and Health Secretary (Jeremy Hunt), urgently, this week, to get assurance that not only will Billy’s meds never again be removed, but to call for an urgent review of the overall policy on medical cannabis as it affects everyone who could benefit.”

Ms Caldwell, of Castlederg in Co Tyrone, Northern Ireland, had seven bottles confiscated at Heathrow Airport customs on June 11 after she brought them in from Toronto.

The emergency measure allowed for one to be returned and Ms Caldwell reported an improvement in her son’s condition after taking the drug, but when this runs out a new application will have to be made for a licence.

“He has 20 days worth of anti-epileptic seizure drugs. What happens after that? Another battle?” Ms Caldwell said.

Many other countries, including much of the US, Germany, Italy and the Netherlands, have legalised the substance’s use medicinally.

But the UK has not, leading Ms Caldwell to claim Britain is “stuck in the 1970s” in its attitude to drug policy.

Ms Caldwell credits the oil with keeping the boy’s seizures at bay, saying he was seizure-free for more than 300 days while using it, but it contains tetrahydrocannabinol (THC), which is restricted in the UK.

Crispin Blunt, an MP who co-chairs an all-parliamentary group on drug policy reform, has described the current stance on marijuana’s medicinal properties as “crazy”.

“We need to get serious now about getting the benefits of these medicines, and move to change the frankly absurd position we are in,” he said, according to the BBC.

Former drugs minister Norman Baker has described the confiscation as “cruel and inhumane”, and renewed calls for a law change.

“It became very clear to me in my time as drugs minister that cannabis has useful medical properties and, indeed, that it is the only substance that works for some people, a situation widely recognised in other countries,” the Liberal Democrat said.