According to the Vatican, a priest who was born in Liverpool would stand in for the Pope during the Queen’s burial.
Archbishop Paul Gallagher, a high-ranking Vatican official, will travel from Rome to attend the Westminster Abbey liturgy on Monday.
When the late Queen visited the Italian city in April 2014, Pope Francis granted her a private audience.
The Vatican’s secretary for relations with nations and international organizations is archbishop Gallagher, 68.
The archbishop attended St. Francis Xavier School in Woolton and graduated in 1967. He was ordained a priest in 1977 and entered the diplomatic service of the Vatican seven years later.
Along with Australia, he has worked for the Holy See in Burundi, where his home was destroyed in 2008, as well as Tanzania, Uruguay, the Philippines, and Tanzania.
He was sent by the pope to Ukraine at the start of this year for an investigation.
In her capacity as queen, the Queen interacted with five popes: John XXIII, Paul VI, John Paul II, and Benedict XVI, meeting the latter two on their trips to the UK.
She also met Pope Pius XII while she was a princess.