London will face opposition from Russia if it pursues a bid to host the Olympic Games in 2036.
Russia has confirmed it is preparing a bid for the Games, with St Petersburg its leading candidate.
Mayor of London Sadiq Khan pledged to explore staging the Olympics again, following the success of London 2012, in the lead-up to his re-election in May.
Russia’s foreign minister Sergey Lavrov said: “The bids are being prepared. We have several cities. St Petersburg for sure, and I believe Kazan as well.”
The hosts for the next three Summer Olympics have already been decided, with Paris staging the event in 2024, LA in 2028 and Brisbane in 2032.
Russia was banned from bidding for the 2032 Games after being found guilty of running a state-sponsored doping programme.
Khan announced in May that London could bid for the 2036 or 2040 Olympics, saying he hoped it would accelerate infrastructure projects including Crossrail 2.
“Not only that, but, by ensuring the games are staged across the UK, and visitors encouraged and supported to explore every corner of our country, London 2036 or 2040 could be a huge boost to levelling up our cities and regions,” he said.
Indonesia has vowed to bid for the 2036 Olympics, while Turkey and India are expected to put forward Istanbul and Ahmedabad respectively.
Russia hosted the Winter Olympics in Sochi in 2014 and last staged the Summer Games in Moscow in 1980.