VATICAN CITY (AP) — Pope Leo XIV prayed Monday in the Vatican with the Archbishop of Canterbury, Sarah Mullally, and vowed to keep working to overcome differences "no matter how intractable they may appear," in a historic meeting with the first female leader of the Church of England and spiritual leader of the global Anglican Communion.

The encounter between Christianity's two most famous religious figures would have been unthinkable just a few years ago, given the divisions between their two churches over women's ordination in general and Mullally's appointment in particular.

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Leo acknowledged that "new problems" in their relationship had been added onto "historically divisive issues." But he nevertheless vowed to continue the tradition of past popes to continue to try to reunite the churches.

Anglicans split from Rome in 1534, when English King Henry VIII was refused a marriage annulment. Despite a formal theological dialogue that began in the 1960s, big differences remain, especially over the Church of England's decision to ordain women. The Roman Catholic Church reserves the priesthood for men.

Leo quoted the late Pope Francis as telling Anglican primates that "it would be a scandal if, due to our divisions, we did not fulfil our common vocation to make Christ known."

"For my part, I add that it would also be a scandal if we did not continue to work towards overcoming our differences, no matter how intractable they may appear," Leo said.

Mullally, whose appointment has split the already divided Anglican Communion, arrived an hour early to meet with Leo. She thanked him for welcoming her on her first foreign visit since she was installed last month.

After meeting in Leo's library, the two then prayed together in the Urban VIII Chapel inside the Apostolic Palace for what the Vatican said was a "moment of prayer." Mullally's office said Leo presided but that they both "said the grace together." The Vatican released photos and video of the meeting and prayer, both of which were closed to the press.

In her remarks to Leo, Mullally said both of them were called to preach the Gospel with "renewed clarity."

"In the face of inhuman violence, deep division, and rapid societal change, we must keep telling a more hopeful story: that every human life has infinite value because we are precious children of God; that the human family is called to live as sisters and brothers," she said. "We must therefore work together for the common good — always building bridges, never walls; that the poorest among us are closest to the heart of God."

A pilgrimage to Rome amid challenges

Mullally is on what she has called a four-day pilgrimage to Rome that has included visits to the main pontifical basilicas, where she has prayed at the tombs of Saints Peter and Paul and met with top Vatican officials.

Lambeth Palace says her visit is designed "to strengthen Anglican–Roman Catholic relations through prayer, personal encounter, and formal theological dialogue. It aims to deepen bonds of communion, affirm a shared witness, and encourage ongoing collaboration at both global and local levels."

The first female Anglican priests were ordained in 1994, its first female bishop in 2015, and now Mullally as the first archbishop of Canterbury.

Leo and Mullally have already exchanged greetings, with Leo congratulating her on her installation last month but acknowledging she was taking over at a "challenging" time and that differences still divide the Anglican and Catholic churches.

He nevertheless vowed to continue dialogue, and in October Leo welcomed King Charles III and Queen Camilla to the Vatican, where they prayed in the Sistine Chapel. Charles is the titular head of the Church of England.

That event, Oct. 25, marked the first time since the Reformation that the heads of the two Christian churches had prayed together.

This year marks the 60th anniversary of the first formal ecumenical statement between the Anglican and Roman Catholic Churches, signed in 1966 at St. Paul's Outside the Walls basilica by Archbishop Michael Ramsey and Pope Paul VI.

Mullally for her part has expressed solidarity with Leo's peace message, after the American-born pope was harshly criticized by President Donald Trump for his calls for peace in Iran.

Popes past have met with female Christian bishops and archbishops: Francis met in 2015 with Archbishop Antje Jackelén, the first woman to lead the Lutheran Church of Sweden. Francis also invited the female Anglican bishop, Jo Bailey Wells, into a private meeting of his cardinal advisers in 2024 to discuss the role of women in the Catholic Church.

An historic meeting that follows the king's visit

George Gross, an expert on theology and the monarchy at King's College London, said Monday's meeting was historic, particularly given the Vatican doesn't recognize the female priesthood.

"If we were to go back several hundred years, it's unthinkable," he said. "It's the fact that the pope is willing to meet, but in itself it also shows the difference, the gap."

Gross said the prayer was clearly an attempt to show the two churches united, especially in confronting the global conflicts and projecting a message of unity. Such optics, he said, were in continuity with the visit to the Vatican in October by the king.

"It's a doubling down of togetherness," he said.

An appointment that divides the Anglican communion

Mullallay's appointment though has split the Anglican Communion, whose 100 million members in 165 countries are deeply divided over issues such as the role of women and the treatment of LGBTQ+ people. Many in England and other Western countries hailed her appointment as a historic breaking of a stained-glass ceiling.

But the communion's largest and fastest-growing churches in Africa belong to a conservative group called the Global Anglican Future Conference, or Gafcon, which has sharply criticized her appointment and threatened a final break. In the U.S., the conservative Anglican Church in North America formed in a break from the more liberal U.S. and Canadian Episcopal churches and has signed onto the Gafcon statement opposing Mullally's appointment.

Mullallay told Leo, who has just returned from a four-nation African voyage, that she would soon be following in his footsteps with a visit to Cameroon and Ghana in July.

"Your pilgrimage to Africa was full of life and joy," she said. "It reminded us that despite our sufferings, people long for life in all its fullness, and countless people are working each day for this vision of the common good."

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