Commuters across Britain have been warned to allow extra time for journeys as wintry conditions start to bite at the start of what could be the coldest week of the winter so far.

Heavy snowfall and icy conditions led to disruption and accidents on the roads with a yellow warning issued for London, the south-east and the east of England until 10am as a band of snow showers moved in from the north-east.

Met Office (@metoffice) Good morning. A widespread frost to start with scattered wintry showers, mainly in the southeast. Elsewhere, dry with sunny spells. A band of rain, sleet, and snow will move into the northwest by dusk and continue southeastward overnight. https://t.co/a70feA0Qeq ^Alex pic.twitter.com/dv6gtOrwGY

Kent police urged motorists to take care and allow extra time for journeys as officers responded to crashes on the M20 near Maidstone. The force tweeted there was heavy snowfall affecting the M20 and said conditions were poor on a wider part of the network.

“Be aware. Extra time. Allow space watch for changing road conditions. If you get stuck stay with your car leave engine running. If you are able, Low gear low revs keep moving,” the force tweeted.

Another yellow warning for ice has been issued covering the east Midlands, east and north-east England and Yorkshire and Humber.

Meanwhile, another snow and ice weather warning has been issued for Wales, Northern Ireland, most of Scotland and northern England, beginning on Monday night from 8pm and continuing until 3pm on Tuesday.

Forecasters said snow was likely to be confined to hills above 100 metres over Northern Ireland and low levels elsewhere. Between 1-3cm of snow was possible away from the coasts, with up to 5cm predicted above 200 metres.

The Met Office forecaster Craig Snell said the first full week of February would be cold. “Plenty of dry weather around, but many places will probably see some snow at some point during the week, but for a lot of us not really amounting to much at all,” he said. “Probably one of our coldest weeks of this winter so far.”