Pope Francis has issued a decree elevating the liturgical celebration in honour of St. Mary Magdalene, placing the latter in the same rank as Christ's Apostles.

The decree was signed by Cardinal Robert Sarah and Archbishop Arthur Roche, respectively the president and secretary of Vatican's Congregation for Divine Worship and the Discipline of the Sacraments, the Catholic News Agency (CNA) reports.

Roche said the papal decree elevates the liturgical celebration honouring Mary Magdalene from a Memorial to a Feast in recognition of her being "the first witness of the Lord's resurrection."

The archbishop said Pope Francis also issued the decree to emphasise the importance of this woman "who so loved Christ and was so greatly loved by Christ."

"She is the witness to the risen Christ and announces the message of the Lord's resurrection just like the rest of the Apostles," Roche said on Friday, the same day the decree was published.

For this reason "it is right that the liturgical celebration of this woman should have the same rank of Feast as that given to the celebration of the Apostles in the General Roman Calendar," the archbishop added.

Roche called Mary Magdalene "an example and model for all women in the Church."

On the Catholic Church's liturgical calendar, saints are honoured with either a "Memorial" a "Feast," or a "Solemnity." Solemnities rank the highest, with Feasts coming in second followed by Memorials, according to CNA.

Mary Magdalene's Feast is set every July 22 of the year.

Roche said the decision to honour Mary Magdalene with a Feast "seeks to reflect more deeply upon the dignity of women, on the new evangelisation and on the greatness of the mystery of God's Mercy."

He said Mary Magdalene "is an example of a true and authentic evangeliser" for being the first person to see Jesus' empty tomb and to hear the truth about the Lord's resurrection from Jesus Himself, and as the first person to announce this message to the Apostles.

Although some people view Mary Magdalene as either a prostitute or the wife of Jesus, Western Christianity since the time of St. Gregory the Great has traditionally identified her as the sinful woman who anoints Jesus' feet with fragrant oils and washes them with her tears; Mary of Magdala; and Mary, the sister of Lazarus and Martha of Bethany, according to CNA.

Regardless of people's views on who she was, Roche said "what is certain is that Mary Magdalene was part of the group of Jesus' disciples; she accompanied Him to the foot of the Cross and, in the garden where she met Him at the tomb, was the first witness of Divine Mercy."

The archbishop called Mary Magdalene as "the Apostle to the Apostles" – a phrase first coined by St. Thomas Aquinas.