The government is planning to relax key Covid-19 restrictions for delegates to the UN Cop26 climate conference to be held in Glasgow for two weeks this November.
Delegates from 196 countries are expected to attend the talks, viewed as one of the last chances for the world to agree limits on greenhouse gas emissions that would avoid the worst ravages of climate breakdown.
The government has offered vaccines to countries coming to the talks, to enable all delegates to be fully vaccinated before the event. However, officials were unable to say how many had taken up the offer.
Those who are fully vaccinated and from red list countries will have to self-isolate for five days in hotels on arrival, and for 10 days if they are unvaccinated. Most attendees are expected to arrive through London.
All vaccines – most of which require two doses to give full protection – will be recognised by the government for the purposes of the event. Attendees will also be tested frequently throughout the event, but additional booster vaccines will not be required.
There will be no requirement for Cop26 attendees coming from amber or green list countries to self-isolate on arrival in the UK whether vaccinated or not, officials said.
As many as 30,000 were originally expected at the talks, which were set to take place last November, but had to be postponed by a year owing to the Covid-19 pandemic. Only about 20,000 are now expected at what will be the biggest diplomatic meeting on UK soil since the second world war, and the biggest UK-hosted public event since the 2012 Olympics.
Scientists warned on Monday, in a landmark report, that extreme weather caused by human actions was now widespread across the world and would get much worse unless countries take drastic action to cut emissions now. At Cop26, regarded as the most important climate talks since the Paris agreement was signed in 2015, countries will be asked to come forward with new commitments to reduce their carbon output in line with scientific advice.
The government has been determined to ensure a physical event rather than a virtual one, a stance praised by veterans of the UN talks, who said forging an international deal would be impossible without face-to-face negotiations.
Alok Sharma, the UK minister in charge of the talks, was heavily criticised in the Daily Mail and other media last Friday for flying round the world to meet other governments, racking up air miles and visiting red list countries without quarantine on his return, under exemptions approved by the government. However, Cop26 experts and green campaigners defended his actions, saying the trips were necessary to gain the trust and forge the relationships necessary for a successful outcome to the crucial talks.
Some of the preliminary negotiations for Cop26 have taken place online, but many countries were reluctant to commit to formal decisions without in-person talks.
Cop26 will open officially on Sunday 31 October, a day earlier than first planned, though world leaders will not arrive until Monday and Tuesday. The conference will continue for two weeks of intense negotiations, ending officially at 6pm on Friday 12 November, although based on previous years it is likely the talks will overrun by a day or more.
Many developing countries are likely to send only small delegations of a few people, but for larger countries such as the US, China and Europe, the delegations could run to more than 100 people. As well as the country delegates, representatives from business, the media, and civil society organisations around the world will be expected to take part.
In previous years, a few developing countries have registered large numbers of delegates who played no role in the proceedings. It is understood the UN will oversee the process to try to ensure there is no abuse, and any delegates found not to be involved will be judged to have invalidated their visas.