The London marathon could be split across two days next year to reportedly allow up to 100 000 runners to participate and raise millions more for charity.
A world record 1.1 million people applied via a ballot to take part in the 2026 London marathon, taking place on April 26, nearly doubling the number of applications from two years ago.
The 2025 event set a world record for number of finishers in a single marathon at 56 640 and raised £87.3 million for a diverse range of charities.
"The TCS London Marathon is the world's most popular marathon, and we are continually exploring innovative ways to enable more people to take part, while delivering positive benefits for London," organisers said in a statement to AFP.
"Together with our partners and stakeholders, we are looking at the intention for the 2027 TCS London Marathon to take place across two days.
"No approval has been given at this stage."
The Guardian reported that the elite men's and women's races would also be staged on separate days if that plan came to fruition with hopes an expanded event could raise £130 million for good causes.
A spokesperson for the Mayor of London, Sadiq Kahn, said: "London is the sporting capital of the world and the Mayor looks forward to working with London Marathon partners to consider if it might be possible to host an event that will run across two days next year."