A government minister appeared to suggest that the mother of a child with severe epilepsy should illegally bring medical cannabis into the country, it has emerged.

The potentially life-saving medicine is effective for a number of treatment-resistant conditions and will have been legal for a year on Friday. But, despite health secretary Matt Hancock’s assurances that it would be available on the NHS within several months, there has not been a prescription for full-extract cannabis oil on the NHS reported since its legalisation. Doctors have effectively been blocked from prescribing it due to a lack of clinical evidence.

Now, it can be disclosed that then junior health minister Seema Kennedy appeared to suggest to a mother that she could flout the law by buying medical cannabis overseas and bringing it into the UK without a licence, which would be illegal.

Joanne Griffiths, whose son Ben’s seizures fell from 100 a day to 10 after he began taking medical cannabis at a cost of about £6,000 a month under private prescription, says that, at an event with Kennedy in June, she voiced her concerns over potentially criminalising herself. But she says Kennedy appeared to dismiss her anxieties, and seemed to suggest she should go ahead.

He would go back to hundreds of seizures a day, suffering horrific injuries and probably die Joanne Griffiths, mother

Asked whether Kennedy, now the immigration minister, stood by her comments, a government spokesperson said: “The minister is clear that at no point did she advocate for her constituent to break the law and fully endorses the government policy. It is unlawful to import cannabis-based products for medicinal use to the UK without a Home Office importation licence.”

However, according to a recording passed to the Observer, Kennedy told Griffiths that bringing the products into the country was one of her options. “So the options, I guess, open are import licence, what else [sic] options? Go and travel or get somebody to travel and bring it in,” said Kennedy.

In April, medical cannabis confiscated at an airport from Emma Appleby – whose nine-year-old daughter Teagan has Lennox-Gastaut syndrome, which can cause up to 300 seizures a day – was returned by the department of health after about a week. When Griffiths raised her concerns, Kennedy is heard saying: “Well, you say that, and of course, I suppose strictly speaking, but I think with – I can’t remember Teagan’s mum’s name – they were released quite quickly, weren’t they?”

Griffiths, who is one of a number of parents lobbying the government for wider access to medical cannabis, said that she had told Kennedy she would record their conversations. But the MP was unaware she was being recorded. Griffiths, whose application for an import licence was later rejected, went abroad and returned with the medicine without informing border guards. She said she did this because she feared her son – who has such severe epilepsy that he often wears a helmet – would die if he could not have the medicine.

“He would go back to hundreds of seizures a day, suffering horrific injuries and probably die,” Griffiths told the Observer. “That’s the reality of it. That amount of seizures does irreparable damage to his brain.”

Facebook Twitter Pinterest Joanne Griffiths and son Ben, whose seizures are so bad that he has to wear a protective helmet. Photograph: Courtesy of Joanne Griffiths

Frustrated at the political and legal impasse, families have accused companies and middle-men of profiteering from prohibitive prices for privately prescribed full-extract cannabis oil. A number of families have threatened to go on hunger strike, and to camp outside 10 Downing Street, if free access is not widened by 1 November.

“We’re not prepared to wait any more,” said Griffiths. “We need urgent intervention now, but the authorities are failing us on every single level. I’ll hunger strike for as long as it takes, until our children get the medicine they need.”

SNP MP Ronnie Cowan, the vice-chair of the all-party parliamentary group on medical cannabis under prescription, said that Kennedy’s remarks showed that she understood how parents were being forced into illegal situations, and urged her to help make medical cannabis free on the NHS as soon as possible.

“For many people this is a matter of life or death,” he told the Observer. “They should not be fobbed off with faint promises or encouraged to break the law.”

On Wednesday, Boris Johnson was asked by Cowan when children suffering from epilepsy would be able to access medical cannabis legally and at no cost.

In his response, the prime minister did not refer to prescriptions of cannabis-based medicines such as Sativex and Epidiolex, which have been provided to patients but are said not to be as effective as full-extract oil, which has a higher THC content – the psychoactive component of cannabis.

He told the House of Commons he understood that people in need of medical cannabis were going through “desperate difficulties”.

“The chief medical officer and NHS England have made it clear that cannabis-based products can be prescribed for medicinal use. It must be up to doctors to decide when it is in the best interests of their patients to do so,” he said, before appearing to offer a meeting to provide further reassurances.

However, Griffiths gave his remarks short shrift and said the prime minister had yet to respond to campaigners’ letters.

“They’re standing up in parliament and saying clinicians can prescribe, but the NHS trusts are not allowing it. This is why we’re being forced to do a hunger strike to bring this to Boris Johnson’s attention for him to urgently intervene.”

On Friday, Kennedy, MP for South Ribble, announced she would stand down at the next general election. The mother of three said she would be focussing on other priorities in her life.