The conclave to select the next pope has begun after Catholic cardinals from across the world filed into the Sistine Chapel Wednesday before sealing themselves inside.

As the papal conclave is set to begin to elect a new pope, the eyes of the world are on the Sistine Chapel, which will hold the Catholic cardinals as they cast their votes for the next leader of the Church.

Black smoke poured out of the Sistine Chapel chimney on Wednesday, signalling that no pope had been elected as 133 cardinals opened the secretive, centuries-old ritual to choose a new leader of the Catholic Church.