The new archbishop of Canterbury has formally taken up his post as the leader of the world's 80-million-strong Anglican Communion.

The Most Rev. Justin Welby swore allegiance to the queen as he accepted the position amid prayers for him, his wife Caroline, and their five children.

The election of Welby, a former oil executive, comes at a difficult time for the Anglican Communion, whose global membership includes the U.S. Episcopal Church.

The communion has been riven by bitter disagreements over female bishops and church teachings on gay relationships.

Welby succeeds Rowan Williams, who retired in December after a decade in office.