Pope Francis has advised against pessimism as many people emerge from coronavirus lockdowns to a new way of living.

During Mass in St Peter's Basilica to mark Pentecost Sunday, Francis noted a tendency to say "nothing will return as before". That kind of thinking, he said, guarantees "the one thing that certainly does not return is hope".

He took to task his own church for its fragmentation, saying it must pull together.

"The world sees conservatives and progressives," he said, but instead all are "children of God".

Telling the faithful to focus on what unites them, he added: "In this pandemic, how wrong narcissism is. The tendency to think only of our needs, to be indifferent to those of others, and to not admit our own frailties and mistakes.

"At this moment, in the great effort of beginning anew, how damaging is pessimism, the tendency to see everything in the worst light and to keep saying that nothing will return as before.

"When someone thinks this way, the one thing that certainly does not return is hope."

A few dozen faithful, wearing masks and sitting one to a pew, attended the ceremony as part of safety measures to avoid spreading Covid-19.

While the Vatican has reopened the basilica to tourists, the rank-and-file faithful are still not allowed to attend Masses celebrated by the Pope to avoid crowding.