The British government has urged top sponsors of the International Olympic Committee not to support the return of Russian and Belarusian athletes to international competition, amid Russia's invasion of Ukraine.
The IOC announced in January that it was exploring ways for Russian and Belarusian athletes to compete internationally as neutral athletes.
Britain's department of culture, media and sport said on Saturday that a letter had been sent to the UK-based chief executives of 13 of the 15 worldwide partners for the 2024 Paris Olympics. The partners include Japanese firms.
The letter asks them to urge the Olympic body to address the British government's concerns over the stance on Russian and Belarusian athletes.
Last month, more than 30 countries including Britain, the US and Japan issued a joint statement. They said they were strongly worried about the feasibility of allowing Russian and Belarusian Olympic athletes to compete as "neutrals" when they are directly funded and supported by their states.