The Covid-19 pandemic is "far from over", an expert has warned.
Dr David Nabarro, the World Health Organisation's (WHO) special envoy on Covid-19, said coronavirus is "surging forward" in most parts of the world.
Addressing a Royal College of Physicians of Edinburgh symposium, he said new variants will be a "regular" occurrence while the virus is still prevalent around the world.
"The pandemic is nowhere near finished," he said.
"Each week we have seen four and a half million cases being reported and know those are an enormous underestimate.
"And we are still seeing a really significant number of deaths - nearly three million.
"What I want to stress is that the pandemic is surging forward everywhere.
"The current UK situation is going against the trend of the global advancement... but please do not think this pandemic is over because it is not.
"With (cases) occurring at a local level, if they are not suppressed they lead to surges of disease and then explosive outbreaks."
Dr Nabarro said it is "one of the fastest spreading viruses" he had ever worked with, but added: "The doubling time (of infections) has slowed massively through the behaviours of people - though physical distance, masks, better hygiene and isolating to avoid transmission."
On the lifting of restrictions in the UK and the success of the vaccination programme, he added: "(Some say) this is an opportunity for the UK to emerge from the pandemic, well I say 'perhaps'.
"I have to stress that I am not 100% sure that the world is going to find it to easy to vaccinate itself out of this pandemic because the emergence of variants that are capable of escaping protection of current vaccines.
"With very large amounts of virus around there will be a regular arrival of new variants that are particularly troublesome. That variant problem is going on and on and on as long as we have got a lot of virus around.
"For anybody to say that they are safe because they are vaccinated is more hope than probability.
"We should expect more variants to emerge and escape vaccine protection, that is inevitable, and so globally we should anticipate that this pandemic is going to go on roaring in parts of the world where there are large numbers of people infected."
He said countries can try their best to stop variants by controlling their borders but that is a "short-term measure".
Dr Nabarro said world leaders need to support other countries through a global Covid programme, adding: "If they don't do so I think the prospect of getting collectively ahead of this pandemic in short order are next to zero and we will go on struggling with uncertainty, not just for the coming year but a number of years."
Meanwhile Sir Michael Marmot told the conference: "If we want to deal with Covid-19, we've got to deal with inequalities."
He said that he had previously been asked about high mortality rates from the disease among different ethnic groups, and had advised that more must be done to deal with structural racism.
But referring to the controversial report on race inequalities from Downing Street he added: "(The report found) there is no structural racism... we've got to find some other explanations for these systematic differences."
Referring to how many wealthy countries have fared during the pandemic, he added: "During the pandemic we had the highest excess mortality.
"What's the link between the pre pandemic and the pandemic situation?
"I suggest... poor governance and political culture, social and economic inequalities have been increasing, there's been reduction in spending on public services, we were ill prepared coming into the pandemic and we were unhealthy."
