Patients in England could get routine annual Covid jabs at the same time as their flu vaccinations, the vaccines minister, Nadhim Zahawi, has said, as the government prepares to start the booster programme in the coming days.

Scientists have warned that the NHS is likely to be under significant pressure from other seasonal illnesses as well as Covid-19 infections.

Zahawi said he hoped the booster programme would be the “last piece of the jigsaw” to allow society to continue through the winter without lockdowns.

Speaking to BBC Radio 4’s Today programme he said: “Where possible we will try and co-administer – with one caveat – with flu. GPs and pharmacies, which are the backbone of the vaccination programme, can rapidly vaccinate lots of people.

“This is probably the last piece of the jigsaw to allow us to transition this virus from pandemic to endemic and I hope by next year we will be in a position to deal with this virus with an annual inoculation programme as we do flu.”

Prof Ravi Gupta, a member of the New and Emerging Respiratory Virus Threats Advisory Group (Nervtag), said current Covid-19 figures “do not bode well for winter” and hinted ministers were right not to rule out further lockdowns.

Boris Johnson is on Tuesday to confirm the start of a booster jabs programme for the over-50s, a day after government scientists finally approved vaccinations for older schoolchildren.

Prof Anthony Harnden, the deputy chair of the Joint Committee on Vaccination and Immunisation, which had declined to approve jabs for children on purely medical grounds, admitted the delay in approving the jabs would cause “uncertainty, hesitation and debate” among families.

The chief medical officers of the UK approved the programme for children aged 12-15 on the basis that, though the medical decision was finely balanced, offering vaccination would have the benefits of preventing disruption to education.

“I think the public in the end will appreciate our honesty and I think they will also appreciate the CMOs’ perspective, and the government offering them choice,” said Prof Harnden. “Sometimes life isn’t black and white, and this is one of those situations.”

Zahawi said children would only be able to choose to have the coronavirus vaccine against their parents’ wishes following a meeting with a clinician.

“On the very rare occasion where there is a difference of opinion between the parent and the 12 to 15-year-old, where the parent for example doesn’t want to give consent but the 12 to 15 year-old wants to have the vaccine, then the first step is the clinician will bring the parent and the child together to see whether they can reach consent,” he said.

“If that is not possible, then if the child is deemed to be competent – and this has been around since the 80s for all vaccination programmes in schools – if the child is deemed to be competent, Gillick competence as it is referred to, then the child can have the vaccine.”

Johnson will set out his “winter plan” on Tuesday afternoon – intending to send a signal that lockdowns will be a last resort by removing some powers in the Coronavirus Act to disrupt businesses and mass gatherings. However, most lockdown powers derive from the Public Health Act 1984.

In a press conference the prime minister will highlight the need to keep some measures in reserve, and will announce a “tool kit” of measures to control the virus which could be introduced – such as a return to compulsory mask-wearing in some settings and telling people to work from home where possible.

Zahawi said: “Lockdowns would be an absolutely last resort. We’re about to embark on a massive booster campaign and of course a flu vaccination programme. I am concerned about flu, we haven’t had much flu circulating anywhere in the world, and in a bad year we could lose up to 25,000 people to flu.”