The 17-year-old was a sought-after target this summer, as Leicester continued to tumble down the leagues, and City had to hold off late transfer interest from Premier League champions Arsenal.
The final deal reportedly cost City £10M up front, with a further £2.5M in performance-related add-ons, as part a five-year contract until 2031.
Monga is the third youngest Premier League player of all time, making his top flight debut against Newcastle at just 15 years and 271 days, and he's highly expected to become a top-flight fixture in future.
However, after not being involved in any of City's first-team matchday squads so far this season, Enzo Maresca is now ready to let him go for a year, to continue his exciting development in the EFL Championship.