The delayed tournament kicks off in Rome on Friday with a total of 24 teams playing across 11 cities.
UEFA has a contingency plan to replace Wembley Stadium as the host for the final of Euro 2020 unless the British government agrees to exempt travelling foreign fans from 10-day quarantine rules, it said on Friday.
Tournament organisers have been in negotiations with the government since it postponed plans to end COVID-19 restrictions on June 21.
The Times newspaper reported on Friday that Budapest was the alternative venue being considered if Wembley was not able to accept travelling supporters.
The London stadium is scheduled to host both semi-finals and the final.
“There is always a contingency plan but we are confident that the final week (of matches) will be held in London,” UEFA said in a statement.
European football’s governing body said discussions with local authorities centred on allowing fans of participating teams to attend matches “using a strict testing and bubble concept that would mean their stay in the UK would be less than 24 hours and their movements would be restricted to approved transport and venues only”.
UEFA said it understood the pressures the government faced. It hoped discussions would reach a “satisfactory conclusion” and was delighted that capacity at Wembley was scheduled to go up to at least 50 percent for the knock-out round matches.
Moscow fan zone closed
Meanwhile, Moscow has closed its Euro 2020 fan zone and banned gatherings of more than 1,000 because of a spike in COVID-19 cases, the mayor of the Russian capital said.
“I didn’t want to do this, but we have to,” Sergei Sobyanin wrote on his website on Friday, a day after saying that cases in Moscow had nearly tripled in just days.
“Starting today, we will limit mass events to a maximum of 1,000 people.”
“We are temporarily stopping all mass entertainment events and we’ll also have to close dance halls and fan zones,” he wrote, referring to the Euro 2020 fan zone outside of the Luzhniki stadium in Moscow.
On Thursday Sobyanin said that the caseload in Moscow, the metropolis of 12 million that has been the epicentre of the COVID-19 pandemic in Russia, soared from 3,000 to 7,000 within a few days and was expected to hit more than 9,000 on Friday.
“It’s tripling, there’s an enormous dynamic that we have not seen during the previous waves,” Sobyanin said during a video conference, adding that new variants were likely to blame.
On Wednesday, Sobyanin had ordered mandatory vaccinations of all service industry workers in Moscow and last weekend announced a “non-working” week in the capital.
Russia’s second city of Saint Petersburg, the country’s worst COVID hotspot after Moscow, is hosting seven Euro 2020 matches – including a quarter-final – and is expected to see thousands of football fans from Europe.
On Monday, Saint Petersburg also announced a tightening of restrictions, including no food sales in its fan zones.