Neighbours are being urged to check on vulnerable people over the next couple of days as temperatures look set to plunge below freezing.

The Met Office has issued a cold weather alert covering Kent, which will last from 6pm this evening (Sunday) until 6pm on Tuesday.

Temperatures could fall to minus 3C at night and a heavy frost is expected.

The yellow alert warns the severe cold could increase the heath risks of vulnerable people and interrupt the supply of services.

The cold snap will cover the whole of England, with the West Midlands expected to be the worst-affected.

The Welsh borders will also suffer, but Scotland will escape the worst of the weather.

The UK Health Security Agency advises pensioners and people with underlying health conditions to keep their heating on to a minimum of 18C, and is encouraging friends and neighbours to check on vulnerable people during the cold snap.

Dr Agostinho Sousa, a public health consultant, said: “Cold weather can have serious consequences for health, with older people and those with heart or lung conditions particularly at risk.

“It’s important to check in on family, friends and relatives who are more vulnerable to the cold weather.

"If you have a pre-existing medical condition or are over the age of 65, it is important to try and heat your home to at least 18C if you can.”

The severe weather is due to a bout of high pressure over the UK.

Day-time temperatures are expected to rise to around mid-single figures - about normal for the time of year.

Met Office meteorologist Dan Stroud said: “We are expecting a cold front to sink south during the course of Saturday and it is going to really help clear the clouds.

“It is going to allow overnight temperatures to dip below zero and we are likely to see an increasing risk of overnight frost as we move into the early part of next week.

“Wrap up warm and close your curtains in the evening to help keep in the heat.

“Daytime temperatures will be responding to the sunshine… we are likely to see them go to about average or just below average.”

The UKHSA said if people can’t heat all the rooms they use, they should heat the living room during the day and the bedroom just before going to sleep.

People should wear several layers of thinner clothing rather than one thick jumper, it added.