Francis, who was born in the British Overseas Territory of Montserrat, holds a blistering personal best in the 200m of 19.88 seconds set in Jamaica in 2016.
Francis was set to compete in Rio Olympics under a neutral flag, but due to a minor hamstring injury he withdrew from the event.
According to BBC Sports Francis started the process to transfer his allegiance in August - just before the Rio Olympics - and is now eligible to compete for Great Britain.
Top British 200m sprinter is the 23-year-old Adam Gemili with a personal best of 19.97 seconds. Gemili came took 4th place at Rio Olympics.