Millions of people in England will be waking up to harsher coronavirus restrictions on Saturday as parts of the south-east head into Tier 3.

The change means 38 million people, or 68% of the population of England, are now under the toughest restrictions.

It comes as the latest figures from Sage showed the reproduction number, or R value, of coronavirus transmission across the UK is estimated to have risen to between 1.1 and 1.2.

Prime Minister Boris Johnson refused to rule out the possibility of a third national lockdown for England in the new year, while the Scottish Health Secretary Jeane Freeman said a post-Christmas lockdown in Scotland “remains on the table”.

Here, the PA news agency looks at the situation across the UK:

England

The first rejigging of the new tier system came into force at midnight on Saturday, with Health Secretary Matt Hancock placing more areas under the toughest measures, closing pubs, restaurants and cinemas.

Bedfordshire, Buckinghamshire, Berkshire, Peterborough, the whole of Hertfordshire, Surrey with the exception of Waverley, Hastings and Rother on the Kent border of East Sussex, and Portsmouth, Gosport and Havant in Hampshire was moved to the toughest level of restrictions.

Bristol and North Somerset shifted from from Tier 3 to Tier 2 and Herefordshire went down into Tier 1.

Under Tier 3 conditions pubs and restaurants can only offer takeaway or delivery services and indoor entertainment venues are shut, while Tier 2 allows people to meet in groups of up to six outdoors and hospitality venues to serve drinks with substantial meals only. Under the medium alert level, the rule of six is in place indoors and outdoors and hospitality venues can offer table service until 10pm.

Wales

Wales will go into its third lockdown from December 28, and the entire country is currently under alert level 3 on a four-level system.

Under current rules, people cannot mix socially with people outside their household or their bubble, bars and restaurants are prevented from selling alcohol and entertainment venues are shut.

All non-essential retail will close on the evening of Christmas Eve and all hospitality from 6pm on Christmas Day, but further restrictions for household mixing will only come in after the five days of relaxed measures at Christmas.

Scotland

Scotland currently has a five-tier system, with Aberdeen, Aberdeenshire and East Lothian moving into Level 3 on Friday, the level where most of the country’s cities and major towns sit.

Under Level 3 restrictions, alcohol cannot be served in pubs, restaurants and cafes, and all leisure and entertainment premises must close.

Jeane Freeman was asked what level of restrictions are likely to be in place after the Christmas period, during the Scottish Government’s daily coronavirus briefing on Friday, to which she replied: “Every possible option remains on the table.”

Northern Ireland

Northern Ireland will enter a six-week lockdown from December 26, with Stormont Executive ministers agreeing to close non-essential retail and contact services, as well as restricting the hospitality sector to takeaway only.

No sporting events will be permitted in the first week of the measures, with an overarching message to the public to stay at home.

Currently, two households can form a bubble, restaurants and pubs which serve food can open but must close by 11pm and all shops can open so long as social distancing is enforced.