Thousands of pilgrims from around the world gathered at the Vatican Wednesday as Pope Francis held his first weekly audience in St Peter's Square since coronavirus hit in early 2020.

The 85-year-old was met with cries of "Long live the pope" as he arrived in his white popemobile into the square still decorated with 40,000 flowers laid out for last weekend's Easter celebrations.

"Even if we are Orthodox, we wanted to come: God is the same for all of us, no matter what branch you are," said Dan Stella, on holiday from Romania.

Some of the crowd waved flags from Croatia, Portugal, Spain, France - and Ukraine, a country for which the pope has repeatedly prayed since the Russian invasion nearly two months ago.

On Wednesday, the pontiff thanked Poland for taking in the bulk of the estimated five million Ukrainians who have fled in Europe's worst refugee crisis since World War II.

"May God reward you for your goodness," he said.

The pope's weekly audience traditionally draws thousands of people but has not been held in the vast St Peter's Square since February 2020, when coronavirus hit.

Francis initially delivered his audiences via video link from the Apostolic Library, before holding them in the San Damaso Courtyard in the Vatican, where numbers could be limited.

On Wednesday, the Argentine pontiff smiled and laughed as he blessed pilgrims, although he appeared to be suffering again from the knee pain that has limited his activities in recent months.

Odile Lafarge came from France with her grandson to see him, telling AFP: "He always has a message of peace and reconciliation. Our world really needs that.

"What struck me when we arrived is how many young people there are here.... it shows there is a future, a flame burning in them."