More than 10 million people have had Covid-19 booster jabs, according to new figures, as people were told to get their top-up to help prevent restrictions this Christmas.

Prime Minister Boris Johnson said the milestone was “amazing” as he warned boosters will be “vital” to keep “you and your loved ones protected through the winter”.

Meanwhile, the chief medical adviser at the UK Health Security Agency said the number of deaths among the vaccinated population is on the rise as immunity wanes.

The Prime Minister tweeted: “An amazing 10 million people across the UK have already come forward for their booster.

“We know vaccine immunity wanes over time, so boosters are vital in keeping you and your loved ones protected through the winter.

“Please get this lifesaving jab as soon as you are called.”

In total, 10,062,704 people in the UK have received a top-up jab, according to the Government, with 409,663 receiving one on Saturday.

But about 30% of over-80s and 40% of over-50s in England are yet to receive a booster shot of vaccine, the Department of Health and Social Care said.

People over 50 and those most at risk from Covid-19 are eligible for a booster six months after their second jab.

From Monday, the NHS is changing the booking system to allow people to pre-book a booster appointment five months after their second Covid-19 vaccine, allowing them to get it as soon as they pass the six-month mark.

The latest figures come as chief medical adviser at the UK Health Security Agency, Dr Susan Hopkins, said elderly and vulnerable people who are double vaccinated have started dying, as the immunity provided by the vaccine reduces over time.

She said: “We’re still seeing deaths in mainly the unvaccinated population, but increasingly, because of immune waning effects, there are deaths in the vaccinated group as well.

“It is particularly the older age groups, so the over-70s in particular, but also those who are clinically vulnerable, extremely vulnerable, and have underlying medical conditions.”

Urging people to take up the jab, Health Secretary Sajid Javid said on Sunday that if “we all come together and play our part” then the country can “avoid a return to restrictions and enjoy Christmas”.

He later said: “We know immunity begins to wane after six months, especially for the elderly and the vulnerable, and booster vaccines will top up their protection to keep people safe over the winter.

“I strongly urge everybody who is eligible for a Covid-19 booster or flu vaccine to take up the offer as soon as you can.”

The third jab could also become a requirement to avoid travel restrictions, in a move which may further drive take-up.

Official guidance was updated earlier this month to say the Government “is reviewing the implications and requirements of boosters for international travel certification” and “looking at whether and how booster vaccinations could be included in the NHS Covid Pass for travel”.

The Government said a further 62 people had died within 28 days of testing positive for Covid-19 as of Sunday, bringing the UK total to 141,805.

Separate figures published by the Office for National Statistics show there have been 166,000 deaths registered in the UK where Covid-19 was mentioned on the death certificate.

As of 9am on Sunday, there had been a further 30,305 lab-confirmed Covid-19 cases in the UK, the Government said.