People over the age of 70 who have not yet been offered a Covid jab are being encouraged to contact the NHS to arrange an appointment.
The health service in England has changed its messaging from "we will contact you" to "contact us" for those over the age of 70.
It comes as the government is just days away from saying whether or not it has met its target for offering all people in the top four priority groups the Covid jab before the middle of February.
The priority list, set out by the Joint Committee on Vaccination and Immunisation, currently has nine groups in it.
At the moment the focus remains on the top four groups which include all those over 70, health and social care workers, care home residents, their carers and people deemed to be clinically extremely vulnerable to the virus.
The Prime Minister set a target for all the people in these group to be offered a Covid-19 vaccine by February 15.
In order not to overwhelm the NHS the initial messaging to the public was to wait until the NHS contacted them about their vaccine.
But the health service is now calling for those aged over 70 who have not yet been vaccinated against Covid-19 to contact the NHS to arrange a jab.
They can book their appointments using the NHS website or those unable to get online can call 119.
If a suitable and convenient slot is not available people can also call their GP practice.
Health and social care workers, who are also among the top four priority groups for vaccination, should speak to their employer about arranging their jab.
GP teams have been asked to contact their clinically extremely vulnerable patients.
Dr Nikki Kanani, medical director for primary care at NHS England and a practising GP, said: "The NHS vaccination programme, the biggest in health service history, is off to a strong start with every eligible care home receiving a visit and millions more people being vaccinated at one of over 1,500 centres across the country thanks to the tireless efforts of my colleagues.
"But if you are aged 70 and over, and haven’t yet received your vaccine, please come forward and make an appointment as soon as you can.
"The vaccine is safe, simple, and will offer you and those around you crucial protection against this virus."
Health Secretary Matt Hancock added: "Thanks to the huge efforts of the NHS, volunteers and local authorities we have vaccinated an incredible 12 million vulnerable people so far – including around nine in 10 of all over-70s.
"We are on track to meet our goal of offering everyone in the top four priority groups a jab.
"So far we have said please wait until the NHS contacts you. I now urge everyone aged 70 and over who hasn’t yet had a vaccination to come forward and contact the NHS to book in their jab.
"And if you have grandparents, relatives and friends over 70, please encourage them to book an appointment as soon as possible, so they can be protected against this awful virus.
"Vaccines are the way out of this pandemic and, by ensuring you and your loved ones get booked in for a jab, the NHS can give those most at-risk the protection they need as we continue to fight this disease together."