Pope Francis has approved changes to the way in which healings can be approved by medics as miracles from potential saints.

The rules for the Vatican's Congregation for Saints to approve healings have been tightened, with six experts being needed to approve the miracles and a two-thirds majority required to approve a statement declaring a healing has no natural or scientific explanation. Previously, only a simple majority was needed to approve the statement.

Archbishop Marcello Bartolucci, secretary of the Congregation for Saints' Causes, said: "The purpose of the regulation is for the good of the [saints'] causes, which can never be separated from the historical and scientific truth of the alleged miracles."

Archbishop Bartolucci was commissioned in September 2015 to revise the regulations established by Pope John Paul II in 1983.

The new regulations also state that a miracle "cannot be re-examined more than three times."

Normally, two miracles are required for a candidate to be declared a saint, except in the case of individuals who the Catholic Church declares as martyrs.

Archbishop Bartolucci said the new regulations will further ensure that the consultations will be carried out with "serenity, objectivity and complete security" by the medical experts.

"This regulation obviously concerns only the proper functioning of the Medical Consultation, whose task is always more delicate, demanding and, thank God, appreciated inside and outside the Church," he added.

"Miracles are not marginal events of the Gospel or the causes of saints. Jesus proclaimed the Kingdom of God in word and with 'messianic signs,' that he worked to make clear his identity and credibility to its mission and also to anticipate the final news of the redeemed world. The same is true for saints."