Rugby-mad Boris Johnson will cap off his whistlestop trade mission to Japan by playing the game on the streets of Tokyo.
As the three-day visit draws to a close, London's mayor will take on child and adult players in an informal knockabout to mark the country's preparations to host the next World Cup in 2019.
Mr Johnson will also continue to highlight the benefits of staging major sporting events following London's success as an Olympic city as well as its role in the current rugby tournament as he holds meetings with ministers.
The 2012 Games left the English capital a "sensational legacy", he said.
"We are both Olympic cities and I have no doubt that Tokyo is ideally placed to take our crown - currently unchallenged - as the city that staged the greatest ever Olympic and Paralympic Games."
After test-driving Toyota's new hydrogen-powered car, the Mirai, earlier this week, Mr Johnson will check out the competition at Mitsubishi Motors.
The firm is developing pioneering hybrid technology and the mayor, who admitted to breaking the Japanese speed limit earlier this week, is expected to take the company's new Outlander model out for a spin.