Daniil Medvedev replaced Novak Djokovic at the top of the world rankings for three weeks in 2022Russian and Belarusian players will not be allowed to compete at Wimbledon this year because of the invasion of Ukraine.
Men's world number two Daniil Medvedev of Russia and women's world number four Aryna Sabalenka of Belarus are the highest-ranked players to be affected.
Players from both countries have been allowed to compete on the tennis tour but not under their national flags.
Wimbledon takes place from 27 June to 10 July.
It is understood the All England Lawn Tennis Club (AELTC) will confirm the move later on Wednesday.
Sabalenka reached the semi-finals of last year's tournament, while Medvedev reached the fourth round.
Russian world number 15 Anastasia Pavlyuchenkova - who called for the war to stopexternal-link earlier this year - and 18th-ranked Victoria Azarenka of Belarus will also miss out.
Russia's Andrey Rublev is eighth in the men's standings, with compatriot Karen Khachanov 26th.
They will all still be able to compete at the French Open, which begins in May.
The AELTC, which organises the grass-court Grand Slam, consulted the government in April about whether to allow players to compete.
Sports minister Nigel Huddleston previously saidexternal-link "nobody flying the flag for Russia should be allowed" to play at Wimbledon.
However, WTA head Steve Simon told BBC Sport in March that he did not believe players from the two countries should be banned from tournaments.
Russia was previously banned from defending its Davis Cup and Billie Jean King Cup team titles after the country's invasion of Ukraine - a military operation supported by Belarus.
Olga Savchuk, who captained Ukraine in last week's Billie Jean King Cup tie against the USA, said Russian players should be banned from competing.
"It cannot just be a sanction against 90% of the Russian people and 10% not," Savchuk told the New York Times.external-link
"It has to be even and I think it is collective guilt."
Ukrainian former world number 13 Alexandr Dolgopolov thanked Wimbledon for "stepping up and showing the world an example".
"I believe Russia should be isolated in all possible ways, and the people of Russia have to solve this problem," he told BBC Sport.
The Women's Tennis Association (WTA) and the men's association (ATP) have suspended their combined event scheduled to take place in Moscow in October.
The International Tennis Federation (ITF) has also cancelled its events in the country.
