It remains unclear which patients will be offered a booster jab, the health and social care minister admitted - but he said that final advice from the Joint Committee on Vaccination and Immunisation (JCVI) was expected 'within the next few days'.
Interim advice from the JCVI in June suggested booster jabs could be rolled out to people aged over 70, those who are clinically vulnerable and health and care staff alongside a flu jab from 1 September.
The interim advice suggested the campaign could then widen to cover all people aged over 50, 16- to 59-year-olds in flu or COVID-19 at-risk groups and household contacts of some at-risk patients.
However, later comments from a JCVI member suggested booster jabs may only be necessary for a much smaller group of people.
The lack of certainty over COVID-19 boosters and continuing uncertainty over whether they can be co-administered with flu jabs has left GPs facing difficult choices over how to plan this year's seasonal flu campaign alongside COVID-19 vaccination.
Speaking to Sky News, Mr Javid said: 'I'm very confident there will be a booster programme. In terms of who gets it and when, we are waiting for final advice which could come across, certainly in the next few days, from the JCVI.'
He said the committee had been considering research to determine whether people should receive booster doses of the same type of vaccine they received for their first two jabs, or whether 'mixing vaccines' could offer a benefit. The JCVI has also considered studies into coadminstration with flu jabs.
The health and social care secretary added: 'That work is almost done. Based on the timeline they have given us I am confident we can start the booster programme this month.'
The update came after vaccines minister Nadhim Zahawi told MPs that it was 'too early' to talk about a flu vaccine shortage, despite a delay of up to two weeks in flu jabs reported by the UK's largest supplier.
GPonline reported last week that the delay had forced GP practices to contact thousands of patients to cancel clinics planned for the start of the 2021 flu campaign.
The JCVI has already backed a third dose of COVID-19 vaccine for patients with severe immunosuppression at the time of their first or second dose. However, the committee was clear this should be considered part of the primary vaccination schedule for people in this group, and was not part of the booster campaign.
The UK's four chief medical officers are also considering whether to back COVID-19 vaccination for children aged 12-15, after the JCVI said benefits 'marginally outweigh' risks for this group, but stopped short of recommending a rollout.