The Chicago-born pope said that a gathering of young faithfuls in Rome was a "sign that a different world is possible."

Pope Leo celebrated the largest event yet of his nearly three-month tenure on Sunday, encouraging a crowd of more than a million Catholic young people gathered in a field on the outskirts of Rome to spread their faith.

In his closing blessing for the Jubilee of Youth, Leo remembered the young people of Gaza and Ukraine and other countries at war who could not join their celebration.