A further 1,564 people have died in the UK within 28 days of a positive Covid test - the biggest figure reported in a single day since the pandemic began.

It brings the total number of deaths by that measure to 84,767.

Covid: UK reports record 1,564 daily deaths https://t.co/Gev7xJzy1O

— Hugh Pym (@BBCHughPym) January 13, 2021

Dr Yvonne Doyle, medical director at Public Health England, said there have now been more deaths in the second wave than the first.

The prime minister warned there was a "very substantial" risk of intensive care capacity being "overtopped".

Speaking to the Commons Liaison Committee, Boris Johnson said the situation was "very, very tough" in the NHS and the strain on staff was "colossal".

He appealed to the public to follow lockdown rules, which require people in England to stay at home and only go out for limited reasons, such as for food shopping, exercise, or work if they cannot do so from home.

Similar measures are in place across much of Scotland, Wales and Northern Ireland.