VATICAN CITY (AP) — Looking tired but relaxed, Pope Francis has led his first major public ceremony after a spate of canceled appointments for health problems.

Francis appeared to hold up well Sunday during the more than 90-minute Mass in St. Peter's Basilica to honor Saints Peter and Paul.

The Vatican has played down the cancellations, including one last-minute Friday because 77-year-old Francis had an unspecified "mild" health problem.

Francis, often laughing or smiling, chatted with each of the 24 archbishops kneeling before him to receive a white woolen band symbolizing shared episcopal power.

An hour after the ceremony, he appeared to people in St. Peter's Square from an Apostolic Palace window. He appealed for Iraq's leaders to use dialogue to save national unity and avoid further warfare there.

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