Travellers arriving in Scotland from Greece will have to quarantine for two weeks following a "significant" spike in coronavirus cases.
The change will come into force at 4am on Thursday due to apparent new evidence that COVID-19 is being imported.
In Wales, people coming back from Zante are being asked to self-isolate for two weeks, after seven infections were discovered on a flight from the popular Greek island that landed in Cardiff on 25 August.
Image:Travellers arriving in Scotland will have to quarantine from 4am on Thursday
The request is not mandatory, but the Welsh health minister wants a meeting with political leaders in the other UK nations to agree to add Greece to all their separate quarantine lists.
Holidaymakers are already scrambling to get home, with British Airways charging up to £554 for a seat on Thursday compared to just £139 the same day the following week.
Decisions about adding countries to or removing them from the so-called list of "travel corridors" are usually taken every Thursday, with those where cases are higher than 20 per 100,000 people at particular risk.
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In Greece, the figure is 13.7 per 100,000, according to the latest figures from the European Centre for Disease Prevention and Control.
But Scotland's chief medical officer, Dr Gregor Smith, said there had been a notable number of "imported cases linked to the Greek islands".
Image:Wales is asking people coming from Zante to self-isolate for two weeks
He added that "the flow of travel" and "behaviour we have seen from some of those travellers" meant Greece needed to be added to the quarantine list "on public health grounds".
Anyone who flouts the requirement to fill out a "passenger locator form" so authorities can check they are isolating faces an initial £60 fine that can be raised to £480 for further offences.
A series of European destinations have already been by sudden quarantine announcements this summer, such as Spain, France and Croatia.
Ministers say they need to act quickly so the measures are effective.
But sun-seekers complain that with little notice, they struggle to get home in time if they cannot self-isolate for two weeks due to being unable to afford to take time off work or fears their children will miss out on more school
Dozens of environmental activists have been arrested as they attempted to block MPs from entering parliament on the first day back after the summer recess.
Thousands of protesters from Extinction Rebellion, the climate action group, descended on Westminster today where they aimed to blockade parliament by setting up camp on the roads immediately in front of it.
Activists gathered at sites including Tate Britain, Trafalgar Square, Buckingham Palace and Westminster Cathedral, before marching on Parliament Square.
Police initially prevented demonstrators from blocking the roads, by corralling them in the square. However, by mid-afternoon, hundreds of activists had broken through a police cordon and sat down in the middle of roads, forcing traffic to stop.
Restrictions on visiting other households are being reintroduced in the Glasgow area after an increase in cases of coronavirus.
First Minister Nicola Sturgeon announced the move after 66 new positive tests were recorded in the Greater Glasgow and Clyde area.
The restrictions will apply to people living in Glasgow, West Dunbartonshire and East Renfrewshire.
They will be in place for two weeks, but will be reviewed after a week.
It is estimated that the restrictions will affect more than 800,000 people - 633,120 in Glasgow, 95,530 in East Renfrewshire and 88,930 in West Dunbartonshire.
Ms Sturgeon said the transmission of the virus in the affected areas appeared mainly to be happening inside people's homes and between households.
As a result, people in the three council areas should not host people from other households inside their homes or visit some else's home.
The daily incidence rate of Covid-19 is now almost 33 new cases per 100,000 people in West Dunbartonshire, 22 in Glasgow and almost 19 in East Renfrewshire. The rate for the rest of Scotland is just over 10.
The local lockdown which was imposed in Aberdeen last month had been triggered by a rate of 14 cases per 100,000 population.
The first minister had earlier voiced concerns after the latest figures showed that 66 of the 154 new cases recorded in Scotland had been in the NHS Greater Glasgow and Clyde area.
There had been an average of eight cases a day in the same area in the first two weeks of August.
At least 65 people have been arrested at climate change protests causing disruption across England.
Extinction Rebellion organised national action in London and Manchester to urge the government to prepare for a "climate crisis".
Campaigners were arrested after they sat in the middle of the road next to Parliament Square to stop traffic.
In Manchester, protesters have been urged to "reconsider their actions" following a rise in Covid-19 cases.
Extinction Rebellion said it planned to "peacefully disrupt the UK Parliament in London" with 10 days of demonstrations until MPs backed the Climate and Ecological Emergency Bill.
Other planned events in the capital include a "carnival of corruption", which is due to take place outside the Treasury, and a "walk of shame" near the Bank of England.
Protester Karen Wildin, a 56-year-old tutor from Leicester, told the PA news agency: "I'm here today because I have serious concerns about the future of the planet - we need to put this above anything else.
"Never mind Covid, never mind A-levels, this is the biggest crisis facing us and we need to raise the message as loudly as possible.
"Not a lot has been done on this issue, everyone needs to hear the message."
Sarah Lunnon, a member of Extinction Rebellion, said: "The failure to act on this issue will have a catastrophic impact on the future of us and the generations to come.
"We want to occupy Parliament Square to make our voices heard. Of course we're in the middle of a pandemic but we're balancing the risk, this is the biggest issue facing us."
The Metropolitan Police said Tuesday's gathering could only take place off the main roads at Parliament Square Gardens between 08:00 BST and 19:00.
Boats, vehicles, trailers or other structures were banned from the procession.
The Met said as of 16:00 a total of 65 people had been arrested on suspicion of public order offences.
Met Commander Jane Connors said: "The reason we have implemented these conditions is that we know these protests may result in serious disruption to local businesses, commuters and our communities and residents, which I will not tolerate."
Last year, more than 1,700 arrests were made during Extinction Rebellion's 10-day Autumn Uprising.
In Manchester, a march is planned through the city and Oxford Street has been closed as part of five days of action.
City council deputy leader Nigel Murphy said planned demonstrations "cannot adhere" to social distancing rules.
The city has increased restrictions due to a recent rise in Covid-19 cases.
Mr Murphy said while the council respected "the right to peaceful protest" this should "not be at the expense of local people".
He said: "We are in the midst of a global public health crisis and we would ask demonstrators to seriously reconsider their actions at the current time.
"Manchester is currently under increased restrictions to limit the spread of the virus because the number of cases has been rising. Gatherings larger than six should only take place if everyone is exclusively from two households or support bubbles."
He said the city had one of the "most ambitious carbon targets in the UK" and was "working to become zero carbon by 2038".
A Titanic-themed demonstration was also held in in Southend-on-Sea where protesters said much of Essex would be underwater by 2050
