Most Rev Justin Welby was among religious figures from various faiths to attend a meal at a mosque near Queen's Park, west London.
Writing on Twitter, the Anglican leader said: "Honoured to be invited to share an #Iftar meal at @alkhoei_org in London tonight."
Archbishop Justin was joined at the event by Rabbi Herschel Gluck OBE founder of the Muslim-Jewish Forum, Labour MP Tulip Siddiq and Rev Anton Illin from the Russian Orthodox Church in UK and Ireland.
@JustinWelby at @AlKhoei for a Big Iftar with friends of various faiths. Through hosting an #iftar we find out more we have in common. pic.twitter.com/Hj5wCZhbkq
— TheBigIftar (@TheBigIftar2017) June 12, 2017
The serve was held at the Al-Khoei Foundation mosque as part of the Big Iftar, an initiative encouraging Muslims to invite their friends and neighbours to join them in marking Iftar.
Writing on Twitter, the organisers said: "JustinWelby at AlKhoei for a Big Iftar with friends of various faiths. Through hosting an #iftar we find out more we have in common."
During the holy month of Ramadan, Muslims avoid drinking or eating between sunrise and sunset. Many will break their fast together during an evening meal, called Iftar, at a mosque.