Russian and Belarusian players will be allowed to compete at Wimbledon this year, the All England Club has announced.
This decision comes as the Ukrainian government told athletes they are not to take part in qualifying events for the 2024 Paris Olympics if they have to compete against Russians.
Tennis players from the two countries must sign declarations of neutrality and must not express support for Russia's invasion of Ukraine, while players who receive funding from the Russian or Belarusian states, including sponsorship from state owned or controlled companies, will remain barred.
The same conditions will apply for the other British grass-court tournaments including Queen’s, reversing the decision made by the All England Club and Lawn Tennis Association 12 months ago.
By barring players from Russia and Belarus completely, the two governing bodies went against the rest of tennis and were heavily penalised, with Wimbledon stripped of ranking points, while the LTA was handed a seven-figure fine and threatened with losing its tournaments.
Ian Hewitt, chairman of the All England Club, said: "We continue to condemn totally Russia’s illegal invasion and our wholehearted support remains with the people of Ukraine.
"This was an incredibly difficult decision, not taken lightly or without a great deal of consideration for those who will be impacted. It is our view that, considering all factors, these are the most appropriate arrangements for the Championships for this year."
Wimbledon will face accusations of hypocrisy given the ongoing conflict, and organisers highlighted why they have come to a different decision 12 months on.
Last year they ruled out forcing Russian and Belarusian athletes to sign declarations but now say "extensive engagement with the Government and tennis stakeholder bodies has clarified and developed the form of declarations".
There has also now been a year of players from the two countries competing around the world under a neutral flag without any instances of overt support for the conflict.
There have been incidents – Novak Djokovic's father was caught up, unwittingly he insisted, in a pro-Russia demonstration at the Australian Open, while locker room tensions came to the fore in Indian Wells a couple of weeks ago after Russian player Anastasia Potapova wore a Spartak Moscow shirt on court.
Ukrainian players, who welcomed Wimbledon's stance last year, have spoken out about what they perceive as a lack of support from the tennis authorities.
The threat of further sanctions against the British game was undoubtedly a major factor in the U-turn, with an LTA statement saying: "The effect on British tennis of the LTA being expelled from the tours would be very damaging and far reaching for the game in our country.
"The impact would be felt by the millions of fans that follow the sport, the grass roots of the game, including coaches and venues which rely on the events for visibility and to bring new players into the game, and of course professional British players.
"Our position in support of the people of Ukraine remains unchanged in 2023 as does our concern around the Russian and Belarusian regimes deriving reputational and other benefits by seeking to associate themselves with players.
"There will also be a zero-tolerance approach to any flags, symbols or other actions which support Russia, Belarus or the war from anyone in our venues, including players and spectators."
Wimbledon organisers have also updated their conditions of entry to specifically bar Russian and Belarusian flags and symbols.
The prospect of a Russian or Belarusian winner of one of the singles titles at Wimbledon is fairly high, with Australian Open champion Aryna Sabalenka a strong performer on grass, while Daniil Medvedev has won more matches than any other player on the men’s tour so far this season.
Meanwhile Ukrainian athletes will not be allowed to take part in qualifying events for the 2024 Paris Olympics if they have to compete against Russians, government minister Oleh Nemchinov said.
Nemchinov, secretary of Ukraine's cabinet ministers, said the government's decision was adopted following a proposal by sports minister Vadym Huttsait and that national federations ignoring the ruling could be sanctioned. Huttsait is also president of Ukraine's Olympic committee.
The International Olympic Committee (IOC) issued recommendations Tuesday for the gradual return to international competition for Russian and Belarusian athletes as neutrals.
Athletes from the two countries have been banned from most elite international sporting competitions since last March in the wake of Russia's invasion of Ukraine.
"At a meeting of the government, a protocol decision was made on the proposal of colleague Huttsait that we take part in qualifying competitions only where there are no Russians," Nemchinov was quoted as saying by Suspilne, Ukraine's public broadcaster, on Thursday.
"Accordingly, participation outside these criteria may be grounds for depriving federations of their national status."
The IOC is to make a separate decision on the participation of Russian and Belarusian athletes in Paris at a later date. Ukraine has also threatened to boycott the 2024 Games should they be allowed to compete there.
Ukraine's sports ministry condemned the IOC's latest guidelines on Wednesday, while the head of Russia's Olympic committee has said the IOC's criteria was "unacceptable".
"I want to tell our fellow athletes who are worried that due to the IOC measures and the admission of Russians or Belarusians to competitions, and accordingly Ukrainians will not be able to participate, that their careers will be broken," Nemchinov said.
"But your life and that of your children will remain."
The IOC is reluctant to exclude Russians and Belarusians from Paris for fear of a return to the boycotts of the Cold War era and set out a pathway in January for them to earn Olympic slots through Asian qualifying to compete as neutral athletes.
Some federations have readmitted Russians and Belarusians in competitions but there is also considerable opposition to the IOC's plans from athletes and some European governments.
Additional reporting by Reuters