The first food parcels have begun arriving at the doors of the most vulnerable people self-isolating at home for 12 weeks during the coronavirus outbreak.
An initial 2,000 packages were delivered over the weekend to those who cannot leave their homes as a result of severe health conditions putting them most at risk.
A total of 1.5 million extremely vulnerable people are being asked to shield themselves during the pandemic.
It comes as Prime Minister Boris Johnson is writing to every household in the UK, urging the public to obey the lockdown and stay home during the "national emergency".
The Government expects more than 50,000 deliveries this week - but this could rise to hundreds of thousands of boxes depending on demand.
The packages contain essentials such as toilet roll, pasta, fruit and tinned goods and are being directed to those vulnerable people self-isolating with little support from family or friends.
Communities Secretary Robert Jenrick joined a delivery in Paddock Wood, Kent.
The minister said this weekend "sees the start of extraordinary steps to support the most clinically vulnerable.
"We will support these people at this difficult time, and the scale of an operation like that has not been seen since the Second World War."
While the deliveries will be welcomed, there are major concerns over the mounting pressure on the food banks that routinely serve those unable to buy food ingredients.
Officials say 900,000 have been written to so far to inform them of the steps being taken to ensure they have supplies.
But GPs must contact a further 600,000 who are not on a national register, a Ministry of Housing, Communities and Local Government spokeswoman said.
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