Three more counties are to be placed under local lockdowns on Monday, the Welsh Government has announced.
Neath Port Talbot, Torfaen and Vale of Glamorgan will have tighter Covid-19 restrictions from 18:00 BST on Monday.
It means half of Wales’ 22 local authority areas will be under local lockdowns, as rules come into force in Cardiff and Swansea later on Sunday.
Almost two million people in Wales – two-thirds of the population – will be under local lockdowns.
Vale of Glamorgan council leader Neil Moore said it had not been an easy decision but pointed to the rate of infection rising to 34.4 people per 100,000 in the county borough.
“We have taken a decision today for early and preventative action,” he said.
“One of the main reasons for this is that the sooner we stop the increase in transmission, the sooner the restrictions can be lifted.
“We must now all work together to make that possible.”
Blaenau Gwent on 202 per 100,000 and Merthyr Tydfil at 169 per 100,000 currently have the highest rates of infection.
Neath Port Talbot council leader Rob Jones said: “These restrictions are being imposed to protect public health, to protect you and your loved ones, and to stop people dying.
“Rates are much higher in local authority areas which border our county borough but we are now seeing rising rates here in Neath Port Talbot.
“We need the help of everyone across Neath Port Talbot to prevent the increasing spread of coronavirus and to bring the infection rates back down.”
Mr Jones also urged people against panic buying, adding: “There is no need to be concerned about stocks running low.”
Welsh local lockdown rules mean extended households must end and people are not allowed to leave or enter the council boundaries without a reasonable excuse.
People are allowed to travel outside the area for a limited number of reasons.
These include going to work if they are not able to work from home, to go to school, give care, or buy food or medical supplies.
Blaenau Gwent, Bridgend, Caerphilly, Merthyr Tydfil, Newport and Rhondda Cynon Taf are all under lockdown, as is Llanelli in Carmarthenshire, which on Saturday became the first town to have restrictions imposed which do not apply to the wider county.
Cardiff and Swansea both go into lockdown at 18:00 BST on Sunday.
From Monday evening, almost 1.9m of Wales’ 3.1m people will be subject to local coronavirus rules.
First Minister Mark Drakeford said: “We are now taking further action and placing three more areas under local restrictions in south Wales – Neath Port Talbot, Torfaen, and the Vale of Glamorgan – because we are seeing rising rates in these three areas. These areas also share borders with local authority areas where rates are much higher.
“Introducing restrictions in any parts of Wales is always an incredibly difficult decision for us to make. But we’re acting to protect people’s health and to try and break the chain of transmission and stop the situation from getting worse.
“This is not a regional lockdown – this is a series of local restrictions in each local authority area to respond to a specific rise in cases in each area, which have distinct and unique chains of transmission.”
Welsh Conservative health spokesman Andrew RT Davies said: “The first minister might not want it to be described as a ‘regional lockdown’ but with two million people in the south Wales corridor now under some form of restrictions that’s unfortunately what it is.”
He called for a more targeted approach – “local not regional” – and said there needed to be urgent financial support for businesses affected.