Some vulnerable people who need flu jabs may not now be able to get them before Christmas, Health Secretary Patricia Hewitt has admitted.
Mrs Hewitt blamed doctors for vaccinating the 'worried well'
She told the BBC a surge in demand meant "not necessarily" everybody at risk would be able to get jabs until more are delivered after Christmas.
Contingency supplies were being sent out and GPs with an excess are being asked to share with their colleagues.
But she admitted the shortage meant it was a "worrying" time for some.
Ms Hewitt said: "What we know is that up until a couple of weeks ago, exactly the same proportions of the at-risk groups, particularly the elderly patients, had been vaccinated as had been vaccinated at the same time last year.
"In the last week, I think there's probably been... a real surge in demand.
"Now, by getting the contingency supplies out to the GPs, which we are doing at the moment, more people in the priority groups will be able to be vaccinated before Christmas".
But she acknowledged that "not necessarily" everybody would be able to get their flu jab before the new order comes through in January.
Although every effort would be made to get more vaccines before then, she said.
However, the health secretary stressed that Britain should be proud of vaccinating more people than have ever been vaccinated against flu before.
"There are very few European countries that vaccinate anything like the number of people we do," she said.
"So actually this is something we should be rather proud of, despite the very worrying and frustrating situation that some practices ... have run out already".
Ms Hewitt announced last week that she would be reviewing the process by which yearly winter flu jabs are ordered.
Currently it is down to individual GPs' practices to order the vaccines from suppliers.
The Department of Health said the 14.5m vaccine doses that had been ordered have all been used, which, in theory, should be enough to protect the 11m people deemed to be high risk.
This led Ms Hewitt to accuse doctors of inoculating the "worried well" in the wake of fears about a possible avian bird flu pandemic in humans.
In the meantime, the Department of Health is advising GPs in England to use remaining stocks only on those at highest risk.
Flu is estimated to kill several thousand people each year in the UK and is particularly dangerous for over-65s and people with health problems such as heart disease, asthma and diabetes.