There is no central stockpile of vaccines. They are delivered to surgeries after being ordered by GPs. In England, millions of doses are ordered annually.
The Department of Health (DoH) said in a statement that some areas were experiencing "local supply issues" but added there was "no national shortage" after reports of patients not being able to get the vaccine at their local GP surgeries.
The Scottish Government announced there were "no supply issues" north of the border, with an "additional stockpile" accessible in addition to the million doses already distributed to local doctor surgeries and pharmacies.
Vaccine manufacturer Sanofi Pasteur MSD said the DoH had enquired about the amount of available doses and the UK-licensed drugs that could be used to boost British supplies.
It added that it had also been asked about the amount of other (non-UK licensed) supplies it had in Europe, which could be used subject to regulations.
So far, 14.7 million doses have been delivered across the UK, with 4 per cent of those stocks going to private firms, the UK Vaccine Industry Group said.
The DoH hopes local supply issues can be resolved by surgeries with surplus vaccine offering it to others suffering shortages.