Sadiq Khan made the plea during an interfaith event at St James's Church Piccadilly on Sunday night, where he warned different religious communities can appear mysterious and complicated to others.
Amazing evening @StJPiccadilly. Londoners of different faiths coming together to break fasts for #Ramadan pic.twitter.com/oa4o6wfOaO
— Mayor of London (@MayorofLondon) June 19, 2016
He said many churches have already taken steps to tackle barriers to integration and the Muslim also expressed his appreciation at being able to break his daily Ramadan fast at the church.
St James's welcomed members of different faith groups for the Iftar event, which typically sees Muslims break their daily fasting for Ramadan with dates and a meal.
Sadiq Khan told Premier: "One of the priorities I have got as mayor is social engagement, interaction [and] integration. Often, mosques, synagogues and churches have not opened their doors because no one has asked.
"We have got to mystify stuff that looks a bit complicated or is clouded in confusion and we need to provide clarity.
"St James is a great example; a great church which isn't simply a place of worship. It is a haven, a refuge, a hub. We need to have mosques, synagogues, temples and gurdwaras to also do the same."
Speaking about the role churches are already playing, he added: "I have visited many foodbanks set up by churches. I see the work our churches do with the homeless community.
"What is important, though... is we learn the best of what is happening in London from the churches."