First US pope Leo XIV takes to popemobile ahead of inaugural mass

Pope Leo XIV, the first US pontiff, made his debut tour of St Peter's Square on Sunday in a popemobile, greeting tens of thousands of pilgrims and well-wishers ahead of his inauguration mass. Leo will preside over the ceremony rich in rites and symbols, where he will receive his special papal ring before giving a homily that will set the tone for his papacy. 

In meetings with journalists, clergy and diplomats, he repeatedly called for peace in a world full of conflicts and defended social justice. Italian authorities have deployed thousands of security officers for the event, alongside snipers on rooftops and anti-drone operations.

At the end of the ceremony, the pope will greet the delegations of heads of state, though it is not clear if any of them will also be accorded a one-to-one private audience.